mini trek slash

Trek Slash 9.9 Gen 6 review – a high pivot and idler suspension design, plus a completely new chassis

With 170mm travel and a complex high pivot layout with upper idler wheel and lower guide, trek’s new slash prioritizes bump swallowing and dh capability without sacrificing the ability to be a sorted enduro all-rounder.

Bike Perfect Verdict

Contrary to what you might expect, Trek’s headline shift to a more rearward axle path and more DH-focused suspension doesn’t mean its latest Slash can’t cut it as a well-rounded and efficient enduro rig. I found it engaging and tons of fun when working as intended, but did have some serious issues connected to the added complexity in the drivetrain layout.

Smooth, calm and balanced ride

Whether pedaling or pushing into the suspension for extra terrain speed, the Slash offers great support

Big idler and guide wheels pedal really smoothly

Nimble and maneuverable

Great chassis feel and tidy finish and details with plenty of adjustability

Very quiet and well protected

Drivetrain complexity introduces some potential issues

Own brand Bontrager wheels and tires wouldn’t be my choice

Doesn’t roll as fast as some 29-er enduro bikes

Reverb dropper won’t be long enough for taller riders

No classic, completely bump-erasing, glued-to-the-floor feel of a high pivot

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With its high pivot suspension and idler setup, Trek’s latest multi-adjustable Slash looks a lot like a Session DH bike , and is also about as on-trend for a 2024 mountain bike as you could imagine (except maybe if it was electric too). 

As well as bringing the latest tech from downhill racing, the Slash 9.9 X0 AXS T-Type Gen 6 ups travel closer to DH levels with 170mm at both ends, compared to the 160mm rear on the older version. The all-new Slash frame also has slightly slacker geometry, although the angles are pretty standard ‘enduro bike territory’ and not that radical for a bike that looks this radical. 

With its rowdier attitude, huge idler wheels and a lot of chain going on in the middle of the bike, the latest Slash definitely looks funky and it’s easy to imagine it working best for a downhiller or lapsed freerider who only needs/wants one bike in their arsenal able to access the steep stuff under their own steam. Once I rode this new Trek though, I quickly realized any assumptions of one-dimensional, DH-focused, performance weren’t actually that accurate.

We’re now up to the sixth Slash generation, so plenty of familiar and proven technologies remain like Trek’s OCLV carbon construction and an ABP rear pivot. The frame offers tons of adjustment, including the ability to switch to 29in wheels like the older Slash rather than run the stock MX setup. The mullet wheels here use proprietary Bontrager carbon rims and tires.

Trek pairs RockShox’s new Vivid Air shock and its several inches higher main pivot with a 170mm RockShox Ultimate Zeb fork up front. On this 9.9 model, the chassis is full carbon everywhere with downtube storage and fully tricked out with SRAM electronics, including a T-Type Transmission with Pod shifters and an electric Reverb AXS dropper. 

Despite its headline downhill orientation, the new Slash is still designed for efficient pedaling and climbing and Trek has clearly done a ton of work on the suspension configuration to balance pedaling and descending qualities that I’ll delve into later. The all-new Slash is available in various models, from this high-end carbon fiber version that’s nearly ten grand to more affordable aluminum frames starting just over $4,000 / £4,000. And, because of the added complexity and weight in this new layout, Trek also continues to offer the Gen 5 Slash as a lighter and simpler alternative. 

Design and geometry

Trek’s Slash has consistently evolved year-on-year, but one trademark has always been offering a smooth ride and excellent tracking under braking. Seeing as this is often touted as a major reason engineers choose to adopt a high pivot suspension design, you might question its motives, but with its improved rear axle path and superior bump swallowing, the design has become the one many brands are adopting in the gravity sector for ultimate suspension performance. 

The high pivot here brings the advertised benefits of the wheel moving backwards in the direction of bump forces to enhance momentum and stability in rough terrain and is part of a system using Trek’s ABP (Active Braking Pivot). That final piece allows the chassis to rotate a touch around the rear rotor under braking, so it doesn’t lock up the suspension and the new setup here bolts SRAM’s T-Type rear mech into the frame together with the Boost rear axle. The way it is integrated is all pretty slick (just like the rest of the frame’s finish) and at the back of a hugely protected chainstay, the ABP pivot tightens up around the axle with a cassette tool if you need to service it, which is a pretty neat touch.

The main reason for moving the main pivot higher is for a more rearward axle path, but a drawback of this is impacting the suspension in other ways; most notably increasing the distance between rear axle and front chain ring as the suspension moves. This increases chain growth, which ups pedal kickback (a force pulling the cranks backwards deeper in the travel) and can feed back to the rider as harshness in the leading leg and inhibit free suspension movement. Trek’s (bigger 19t) upper pulley wheel is all about negating this effect and retaining the benefits of a high main pivot. By routing the chain around an idler pulley and controlling the distance between the axle and the high main pivot, the brand can better control any pedal kickback. 

And, yes, all this adds all the drivetrain complexity you can see when combined with an extra lower guide for chain stability. But while Trek’s previous Slash saw anti-squat dip to 20 percent by the end of the bike’s travel, its engineers have delivered 100 percent anti-squat throughout the travel on this Gen 6 model using the new complicated suspension layout. Consistent anti-squat throughout the travel means the Slash should pedal efficiently without bobbing anywhere while climbing or sprinting and (equally importantly) have a consistent and predictable feel in terms of support and speed generation in compressions and berms.

Combining this aspect of tuning with the rear ABP pivot that helps control anti-rise by partially rotating as the bike reacts to braking forces on the suspension (and how much it wants to extend up under braking), gives Trek’s boffins a potent recipe for tweaking suspension performance under pedaling, braking and bodyweight inputs.

In terms of construction, this 9.9 level frame is carbon throughout with a shock rocker that’s part magnesium, and uses Trek's OCLV carbon technology, which improves strength and impact resistance by better compressing carbon layers and purging fillers. 

Trek keeps the old(er) school stuff where it makes sense, including the 73mm BSA threaded bottom bracket and internal cable routing that avoids annoyingly going inside your headset bearings like plenty bigger brands are doing. The Slash cable routing minimizes tube rattle to the point it’s non-existent and also maximizes internal frame space inside Trek’s downtube stash. 

Alongside the very chunky sculpted chainstay guard, there’s a metal plate on the interior of stays where the chain can potentially slap and rub against the carbon and even an impact-resistant laminate under the paint for extra durability everywhere. Slash stays can handle fatter rubber (up to 2.6in), offer good mud clearance and a mud guard, and there’s more frame protection behind the BB and under the downtube where removable plastic guards defend against rock strikes and shuttle damage. 

Gen 6 Slash comes with a 170mm fork that gives a slightly slacker 63.3-degree head angle, but it’s also rated for up to 190mm fork if you want to go full ham on the downhills or hucks. You can adjust the head angle without changing fork stroke too with Trek’s aftermarket adjustable headset cups or fiddle with the lower shock mount and flip the leverage rate between less or more progressive. Riding with less ramp up (like I did) offers a plusher feel and a smoother and more supportive mid-stroke, and flipping it makes it more progressive for when you’re riding fast, hitting big features and want extra bottom out resistance (or are running a more linear coil shock).

I found the 77-degree seat angle pretty much spot on for climbing without being too steep to pedal longer distances or feel cramped in the cockpit, and across a broad range of sizes, Slash chainstays grow in length from just under 430mm on the M to almost 440mm on the XL. The M/L I tested had just under 470mm reach and foot-to-hand distances range from 448mm to a rangy 513mm on the biggest frame; all with a 351mm static BB height sounds reasonably tall, but doesn’t feel at all high when you’re actually riding.

Components and build

This Slash 9.9 model costs nearly ten grand, so it’s a shame that quite a few parts here had Bontrager written on the side. I didn’t like the grips’ uncomfortable lock rings, but that’s no big deal, unlike the sketchy SE5 and SE6 tires that really affect performance. Despite a decent tread pattern, the 2.5-inch pair use a finer weave 120tpi casing that lacks damping and protection and makes them too flimsy and thin for serious downhill riding. To top this off, the rubber compound feels perilously slick on wet rocks and roots too. 

During testing, I replaced them with Michelin tires, which offered way better grip and stability, and from what I can see, even Trek’s top enduro racers, like Hattie Harnden, do the same and opt for Continental tires with logos blacked out for World Cup events. Swapping tires is a bit of a must to match the Slash’s DH capability and you’ll need to factor in another $100 / £100 or so for this.

The Bontrager Line Pro 30 carbon wheels are also not to my taste. They proved really strong, constantly hammered into rock slabs on full-on DH tracks and provide a razor-sharp, quick-to-accelerate feel, but this also makes the ride edgy and harsh and lacking in the compliance and tracking many modern carbon rims now offer. I tried to mitigate this effect by reducing spoke tension half a turn, which improved comfort slightly, but one nipple on the rear wheel fully unwound and I had to take Bontrager’s clever, tubeless tape-avoiding, rubberized rim strip off to reseat it.

Trek’s one-piece carbon bar/stem combo looks slick and is lightweight, but it has its downsides too. You can’t adjust stem length or bar shape if the shape and fit don’t suit, but I can’t comment on ride feel as a previous tester had cut it too narrow for me to try. RockShox’s Reverb AXS dropper post maxes out at 170mm travel, which worked well enough for me and (even though it requires charging another AXS battery) the lightness of operation makes it one of my favored droppers, but the tallest riders might want more drop.

On a more positive note, SRAM’s Code SLR 4-piston brakes with 200mm rotors deliver consistent stopping power and the latest T-Type transmission with a 10-52t cassette is rock solid. Even with all the complications, Trek’s drivetrain is surprisingly smooth and delivers seamless shifts using SRAM’s new adjustable Pod shifters, which greatly improved thumb positioning over older designs. I got so used to the Pods in fact that mechanical shifting felt weird and archaic switching back to it, which is the first time that’s happened since electric gears came out. 

SRAM’s 165mm XO1 cranks are stiff and solid and provide extra ground clearance too, but I did have a major issue with the AXS XO1 T-Type rear mech. While it withstood impacts and rock strikes like a champ, the AXS battery was knocked off while riding and completely lost in the forest. Fortunately, I had a spare with me in Italy, but this could be a major problem during your race or ride holiday. The battery’s placement hanging off the back secured by a small plastic tab is a bit of a design flaw SRAM seems to be aware too, as the newer GX Eagle T-Type mech has the battery relocated on top for better security.

Ride, handling and performance

Forget any ideas of excessive drivetrain drag and a soft feel under power; this new Slash pedals and climbs pretty well by any standards, not just compared to other long travel enduro bikes . Even with the complex design, it’s not that heavy for the category either and smooth and zippy while supporting rider weight evenly whether spinning or stomping. 

The seated climbing position is comfy and well-balanced to keep you centered, and the way the back tire maintains traction on steep climbs without wheel-spinning is properly impressive – that rearward axle path is clearly doing something extra and rubbing out small hook ups so the rear tire bites and drives on slippery or loose surfaces stood up or sat down.

Even threading the complicated sequence of 19t upper idler, X-Sync chainring, lower guide and that massive T-Type mech and cassette, the chain is quiet and smooth rolling when properly lined up and the suspension never really wallows or bobs on the downstroke either. I read elsewhere some owners have issues with rumbling, but this bike stayed really quiet for me.

I’m not the biggest fan of climbing and very sensitive to anything slowing me down, but while this clearly isn’t a downcountry bike , it also avoids too much wasted energy, even sprinting along the flat or sneaking cranks in coming up to a big jump or something where some long travel bikes can really bog you down. Wherever you are in the travel, there is a real smoothness to the pedaling too, which backs up Trek’s claims of the near constant 100 percent anti-squat making it pedal more like its 120mm travel Top Fuel .

At this point I could go off on a real tangent and spout my half-baked theory that for flat pedal riders like me, bikes with more consistent (or lower) anti-squat numbers generally pedal more smoothly and with less of a surge/dip cycle that can feel choppy and introduce more bob. Flat pedal riders put more emphasis on the downstroke relative to clipped in riders who spin smoother circles, and I wonder if it’s something bike tuners and engineers (who as experienced or ‘expert’ riders are more likely to be clipped in) take into account, considering how many potential customers ride flats. This theory is definitely something for another day though, and maybe Trek’s engineers agree with me seeing as the new Slash pedals very neutrally anyway.

Trek claims the idler setup does add a small percentage of drag, but I reckon the T-Type drivetrain helps cancel some of this effect too by being super smooth, stiff and perfectly aligned on any bike. I can’t comment on whether the efficiency would be as good on a Slash with lower-tier kit. Despite the sharpness in power delivery, this is still a 170mm bike though, so I found the active rear end benefits from flipping the Vivid Air into the locked position for longer climbs on tarmac or smooth gravel fire roads where super-active suspension isn’t needed. 

On the downhill and steep tracks where the Slash is most optimized, the suspension design kind of mirrors the pedaling performance. It somehow doesn’t scream ‘high-pivot suspension’ and overly glued to the floor, instead the main sensation is smoothness and control. 

The Vivid shock (or back end) feels fantastic absorbing impacts without ever hooking up, while still supporting rider weight and not feeling bogged down and mushy in the midstroke. This perkiness and on-its-toes feel isn’t ever at the expense of bump swallowing either and the rear suspension is also highly active with excellent ground tracking and the ability to keep working even under hard braking. 

Calm and collected it might be, but the Slash’s handling still lives up to its name by being plenty reactive, making it easy to dart about on technical terrain and execute cutties or Scandi flicks as happily as just smash it down the middle line and rely on the rear travel. It’s pretty easy to manual and pays back when you pump for speed. There’s a great sense of balance between the Vivid and the Zeb too, so you’re never getting pitched about on the steeps or feel like rider weight’s falling off the back. RockShox’s DH air shock is so good, it genuinely feels like a coil spring on ripple hits or sharp edges in terms of muting trail feedback brilliantly, plus it’s obvious what all the adjustments are doing so you can tune it to taste really easily without ever messing up the overall balance or performance too much.

Part of the Vivid’s gentle touch is due to the clever Touchdown design inside, which bypasses any compression damping for the first 10 percent of travel for extra sensitivity off the top and ground connection. Deeper in the travel, the Slash’s rear end controls and dampens impacts with smoothly building support, while feeding back plenty of trail information, so it never feels too dead or limp. 

In terms of handling, the Slash is very neutral but can also react quickly to body weight shifts and little lifts and lofts out of turns or off-trail features. The M/L I tested is slightly shorter than many enduro bikes I review, but with the extra travel and high pivot that sees chainstays grow marginally in the travel, it feels as stable as a larger bike somehow, and I enjoyed the tighter dimensions and slightly more nimble handling. My guess is that the 490mm reach size Large might feel pretty big compared to other Large sized enduro bikes. 

Trek’s Slash factor extends to jumps too, where the bike carves up and pops off lips without feeling soggy, even when set up for a very supple, ground-tracing feel at the shock. One of the best traits of the Slash everywhere is offering loads of smooth support at the back and how it maintains stability and avoids any sensation of the front end feeling a bit light mid turn and rider weight falling off the back a bit, which is something I’ve had before on some MX high pivot bikes.

The Slash’s carbon frame has a new storage cupboard door that’s easier to open and the inside is bigger; the chassis feels solid and stiff too and able to hold straight in hectic lines without harshness or unexpected flexing. There’s also the adjustability for riders to tweak the setup for different riding styles and conditions, but I pretty much liked the Slash out of the box and didn’t even bother messing around with it.

While there are loads of positives to shout about with the Slash’s ride quality, it’s not without some major issues elsewhere. I had some major problems with chain security and the durability of the idler and lower guide setup and I also didn’t like the overly stiff own-brand carbon wheels and puny tire combo that feels too edgy on a bike where you’re likely to be pushing the limits of traction in some gnarly terrain. 

I’m aware all the best mechanical stories start with, ‘I was just riding along’, but doing just that on a loose, rocky trail, either a rock punched the lower MRP guide bouncing up off the front tire or got sucked into it by the rear one and bent it inwards at 90 degrees and wrote it off and the jockey wheel. This same issue happened to a friend on an aluminum Slash too, which suggests the lower guide could benefit from better protection or a thicker aluminum plate to prevent bending.

And this is exactly what you get on the aftermarket MRP replacement Trek sent me, so giving Trek the benefit of the doubt, it may use thinner material to avoid frame damage, but more likely does it to save cash, which is a bit rubbish on a bike this much cash. Setting up the lower idler correctly requires a gap of 10-24mm from the chainstay to the top of the lower roller, with clockwise rotation increasing chain wrap on the chainring and improving chain retention. It worked fine for me once the replacement guide arrived, but I had several weeks of struggling to get this alignment right once the guide got bent.

I had to use a homemade roller guide (made from a grinder disc!) while awaiting a replacement, and then had issues with the upper idler stuffing the chain between the jockey and frame. Trek has since made a rolling revision to lengthen the upper idler teeth for better chain stability, but my test bike didn’t have this update. All this faffing was a bit of pain, but didn’t actually stop me riding to be fair, and I’ve since logged thousands of meters descending on the replacement without problems and ended up kind of forgiving the Slash because it’s been so much fun.

Overall, I reckon the Slash offers the security of a big super enduro bike that can handle chunky terrain and is easy to ride fast and in control, while maintaining the sensory stimulation of a ‘regular’ 160mm-ish enduro bike. This much versatility is hard to find and will make the new Slash a solid option for many riders, not just those totally hell-bent on sending the descents.

More than just a bike for a downhiller who can’t justify having both a DH and enduro bike, Trek’s Slash 9.9 X0 AXS T-Type Gen 6 is a versatile and efficient all-rounder in its own right. The bike rips downhill and can rub out some serious chunk and the suspension offers continuous support to push into and out of for a really well-balanced rider feel front to rear.

A major highlight is how smooth the bike feels in terms of bump swallowing and vibration damping, without ever losing a sharper edge and enough reactiveness to push on and play harder. Pedaling zip and climbing prowess is decent too, especially for a bike carrying some extra weight due to a high pivot design and added drivetrain parts.

The added complexity of the idler and guide setup caused me some big headaches during testing though, and combined with some underperforming own-brand components, as much as I love the ride quality here, it’s difficult to 100 percent recommend this Slash 9.9 as offering ultimate performance and value.

Test conditions

• Conditions: Every kind of trail and every kind of weather
• Terrain: DH test tracks in San Remo in blazing heat to Bike Park Wales blues in rain via local hand cut enduro tracks and loam
• Temperature: Spring/summer UK weather – 10 to 24 degrees Celsius

Tech specs: Trek Slash 9.9 X0 AXS T-Type Gen 6

• Price: $9,399.00 / £9,400.00 / €9,999.00
• Discipline: Enduro
• Frame: Trek OCLV carbon HP w/internal storage
• Shock: RockShox Vivid Air Ultimate 170mm travel
• Fork: RockShox Zeb Ultimate Charger 3 170mm travel
• Wheels: Bontrager Line Pro 30 carbon w/Rapid Drive 108 hubs 
• Tires: Bontrager Team Issue tires 29in x 2.5in front SE6 and 27.5 x 2.5in rear SE5 w/Core Strength sidewalls
• Drivetrain: SRAM XO Eagle Transmission, SRAM XO AXS POD Ultimate, T-Type DUB crank 165mm, XO Eagle rear mech and 10-52t cassette
• Brakes: SRAM Code SLR 4-piston w/ 200mm 6-bolt rotors F&R
• Seatpost: RockShox Reverb AXS 170mm dropper  
• Saddle: Bontrager Arvada saddle
• Bars and stem: Bontrager RSL integrated bar stem w/35mm equivalent stem length and 820mm wide bar
• Weight: 16.2kg (35.7lb) M/L tested
• Sizes: M, M/L, L, XL
• Rider Height: 176cm
• Head angle: 63.3 degrees
• Seat angle: 73 degrees
• Effective seat angle: 77.4 degrees
• BB height: 350mm (MX setting)
• Chainstay: 434mm
• Front center: 821mm
• Wheelbase: 1,254mm
• Downtube: 745mm
• Seat tube: 420mm
• Top tube: 606mm
• Reach: 468mm

An ex-elite downhill racer, Mick's been mucking about and occasionally racing mountain bikes for over twenty years. Racing led to photo modelling and testing kit for magazines back in the day, and, nowadays, he's mostly riding enduro-style terrain on conventional and electric bikes. As curious as ever about products and tech, he's as likely to be on the other side of the lens or computer screen rating, reviewing and shooting all the latest gear. Mick's list of regular clients includes Bike Perfect, MBR, MBUK, and most of the leading UK MTB publications at one point or another.

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TREK SLASH 9.9 X0 GEN 6 REVIEW

Words by Drew Rohde  |  Photos by Staff

After nearly six months of abuse, conversations with Trek Bikes HQ and a YouTube Service Bulletin video full of interesting comments, we’re kicking off the new year with a high pivot, Gen 6 Trek Slash review that should be another great conversation piece as one of the hottest bikes of 2023. We’ve been fans of many of Trek’s bikes over the last few years from the Session DH bike to their Fuel EX and Fuel EXe and of course, the last generation Slash . We first rode the Gen 6 Trek Slash during Crankworx Whistler, where we filmed a Dissected Feature with their engineer: Trek athlete Casey Brown and more. Since then, we spent the rest of summer in the bike park, pedaling backcountry trails and yes, filming a service video on the famous “Chain dropping” issue that commenters had us thinking was affecting nearly everyone who owned one of these bikes. But…as the saying goes, don’t believe everything you hear. Even if you don’t believe what we’ve got to say when it comes to the goods and bads of the new Trek Slash, we think you’ll find it entertaining at least.

QUICK SPECS

• 170mm High Pivot ABP Suspension • Mixed Wheel (29”F/27.5”R) as standard, dual 29” option • HTA 63.3 • STA 76 (effective) • REACH 490 (Large)

FULL BUILD SPEC

CHASSIS Frame: OCLV Mountain Carbon | 170mm Fork: RockShox ZEB Ultimate 170mm | Charger 3 RC2 Shock: RockShox Vivid Ultimate 230x65mm

COCKPIT Brakes: SRAM Code Silver | 200F/R Centreline rotors Bar/Stem: Bontrager RSL Integrated | OCLV Carbon | 820mm | 27.5mm Rise | 35mm Length Headset: Integrated Sealed Bearing Seatpost: RockShox Reverb AXS | S: 100mm, M-XL: 170mm Saddle: Bontrager Arvada

WHEELS Hubs: Bontrager Rapid Drive 108 Rims: Bontrager Line Pro Carbon Front Tire: Bontrager SE6 Team Issue | 29″ x 2.5″ Rear Tire: Bontrager SE5 Team Issue | 27.5″ x 2.5″

DRIVETRAIN Bottom Bracket: SRAM DUB Threaded Cassette: SRAM Eagle XS-1295 | T-Type | 10-52T Cranks: SRAM X0 Eagle | T-Type | 30T | 165mm length Shifter: SRAM AXS POD Ultimate | 12s Derailleur: SRAM X0 Eagle AXS | 12s

Downhill performance is incredible

Rear suspension plush yet solid

Fast and Confident

Bike Park shredder

Vivid Ultimate

WE DON’T

3 Dropped chains (fix appears to work)

Steep, chunky climbing

About The Trek Slash Gen 6

Packing 170mm of travel out back, the new Trek Slash claims to be a 70/30 bike, meaning Trek designed the bike to have a 70% downhill bias with a 30% nod to climbing and uphill capabilities. Needless to say, this isn’t your run of the mill XC or all-mountain bike. It’s designed and built for riders who prioritize downhill speed, composure, and confidence on the gnarliest terrain over efficiency and climbing performance.

Since this review is likely going to get a bit long, we’ll link to our Dissected Feature which has a written interview, all the tech details and a video interview and presentation on the Gen 6 Trek Slash. If you’d like to check that out, click here.

If the CliffsNotes version works for you then we’ll gloss over a few key features:

FRAME AND FEATURES

Updated for 2023, the high pivot Trek Slash Gen 6 can be run with a number of wheel size configurations and can take up to a 190mm travel fork but comes with a 170mm fork and mixed-wheel setup as standard. Riders can choose a full 29er race machine, 27.5” aggro-shredder or put a dual crown 190mm with a mullet and have a mini-Session bike park rig.

With many people loving the last generation Slash, some may have wondered why Trek opted to go to a high pivot and run two idlers? Well, with Trek’s other bikes creeping up in capability and riders wanting to go faster and bigger, it seems many brands are making their bikes bigger and burlier, and of course, more high-pivoty. Trek Slash engineer, Matt Yerke told us that even though the bike’s 70% focused on DH performance, they took time to keep it versatile and pedal-friendly, as a mountain bike should be. Did they deliver? We’ll see down below.

BUILD SPECS AND VALUE  

With bikes starting at $4,399 and going up to $11,499, our Slash 9.9 X0 AXS sits on the higher end of the spectrum at $9,399 and comes with a dialed spec. If we were spending our own money however, we’d likely be checking out the Slash 9 or Slash 9.8 XT models.

Chain Drop Service Bulletin and Notes from Trek

We published this How To Video to address some of the popularized videos and comments talking about chain drop on the new Trek Slash. After publishing this video and seeing all the comments, we reached out to Trek as it had us reconsidering our official stance on the long-term review you’re about to see below. The statement below from Trek, which we are taking as truthful, made us feel better and also aligned with our notions of what we’ve observed. Trek passed our concern around their Customer and Dealer Service teams and below is a small excerpt.

“First off, Trek Bicycles and I would like to acknowledge that it is frustrating to buy a nice new bike that doesn’t work exactly like it should out of the box. Luckily however, it has been a very small number of people affected and thankfully they have been far less upset than what online commenters may have you believe.

Trek’s customer service team has actually received way more calls about internet comments talking about chain drop than actual Slash owners who are experiencing the issue. We have found that a handful of riders said the fix did not entirely solve their dropping issues. We have sent out early units of our updated idler wheel to that handful of riders, one of which is Ryan Howard, who has been spending a ton of time on his Slash. We’ve been pleased to hear that those riders are no longer having any drop issues.

These will ship to dealers at no cost for any Slash owners who want to get one.” – Ross Rushin // MTB Product Manager

When evaluating the new Gen 6 Trek Slash 9.9 X0 AXS against the previous generation Slash and current offerings from other brands in this genre, the Slash commands attention. As with any purpose-built product, the things that make it excel can also alienate or turn off others. I’m traditionally not a huge fan of high pivot bikes, though I’ve grown to like mid-high pivot bikes for certain applications. Rocky Mountain’s Powerplay eBike and the Trek Session , which we reviewed last year, are two examples of mid-high pivot bikes that I like quite a bit.

Chances are you’ve already heard the touted claims of high pivot bikes since they’ve been so heavily marketed over the last couple of years, so we’ll save you the pitch. What is undeniable though, is that they can charge over terrain and obstacles a bit better than other designs, but only if they are tuned and designed well. We have ridden some high pivots that don’t really improve much, but suffer the downsides of a high pivot, but we’re happy to report that Trek has avoided this ill fate.

SETUP | Setting up The Trek Slash was one of the easier tasks of the year. It required almost zero tuning, customization or tinkering with to feel amazing. If you’ve read our older Trek reviews, you may recall us being a bit critical about the tune being a bit too mellow, which led to heavier or more aggressive riders needing to add maximum volume reducers or going our route, contacting Fox Shox to weasel a Trek Factory Racing tuned shock, which did wonders for the bike. This is no longer an issue as Trek seem to have finally identified that if they’re going to design an aggressive bike for aggressive riders, they need to have a shock and tune that are ready for it.

The most time-consuming part of our review bike’s set up was removing the one-piece Bontrager bar and stem combo unit and replacing it with our favorite OneUp Components Ebar and stem. This resulted in a better body position and way less hand fatigue.

DESCENDING | Trek has done a great job of making the new Slash’s suspension absolutely devour hits of all sizes. The RockShox Vivid Ultimate rear shock only compliments the insane capability of the Slash’s rear end. It is possibly the smoothest, best feeling rear suspension I’ve felt in a while. For me, a rider who loves smashing, gapping and floating rough, chunky downhill trails, it offers a very nice platform for support and control, but gets out of the way offering a bottomless and smooth feel. I could have been tricked into thinking a coil shock was mounted out back based on the composure and smoothness.

When it comes to downhill performance, the Trek Slash may be the best descending mountain bike we rode in 2023! It absolutely shreds trails with ease and begs to go faster. Whether we were lapping blown-out end of season bike park trails or remote backcountry downhills, the Slash leads the way. In fact, we can’t think of any bikes that aren’t downhill bikes that we’d want to ride in a bike park more than the Slash. The speed this bike carries, composure over braking bumps, big and little hits as well as the way it corners make it a really impressive machine.

The downside is, the compliance combined with the weight, makes this bike a little bit tougher to jib on smaller features at slower speeds. It absolutely still gets off the ground and is fun to play on, it just requires a bit more muscle to get it up and tweaked. Granted, this rocket ship wasn’t designed with lower speeds in mind, and it shows with a list of Personal Records that our various testers achieved.

Another downside is that the bike does have more stuff to go wrong. Whether you’re one of the unlucky riders dropping chains – which we did three times before the service bulletin addressed the issue – or not, more moving parts, extra chain links, and more nooks and crannies all mean more chances for things to go wrong.

CLIMBING | Along with the above concerns, the climbing performance of the Gen 6 Slash certainly isn’t what its outgoing sibling offered. Since taking possession of the Trek Slash 9.9 XO AXS we’ve had four riders put time on it. Two of which owned previous generation Trek Slashes. All riders agreed, like Trek claims, this bike is a definite 70/30 bike, and the climbing performance is tolerable in certain situations like fire roads and smoother trails, but can be a struggle on more steep, technical trails with larger obstacles that want to eat your momentum.

The weight is noted, and while the drag may be a claimed 3%, it felt a bit closer to 10% in practice. That could be exacerbated by the lengthening rear end – yes, the same thing that makes high pivots so great, also works against it.

It’s been a while since we graduated but, we think someone smart once said something about actions having reactions, but we didn’t pay close attention in school so maybe we’re making it up. Either way, when speeds are low, the grade steep and effort high, we found that the rear end could “stall” as we tried to pedal over roots or rocks, sucking our energy and momentum in the process. Much the way the rear end grows to get up and out of the way of an impact while descending, as you climb and hit an obstacle, the front continues to creep up the hill as you grind away at the pedals. However, the rear wheel goes backwards before going up and that delay can make it feel like you’re pedaling harder to get up and over that obstacle, which means more energy and slower times. Of course, this bike wasn’t designed to race up the hill, it’s meant to go down. If your energy is spent on the way up, however, it could be worth considering you may be more fatigued when that race timer starts.

FINISH AND VALUE | Now, as amazing as the bike is, we did in fact drop the chain three times over the six-month test period we had. Since the repair, we didn’t drop the chain, however we only had a few rides on it before winter hit, so we can’t say with 100% confidence it’s gone, but we are pretty certain that with the updated spacing and especially the new idler wheel, we’d be in good shape. You may want to wait until the updated idlers hit, hopefully February of 2024, but in the meantime the chain dropping issue may not be quite as bad as commenters may have you believing.

The rest of the bike is a nicely put together package. Trek paint had some years known for being a bit, soft we’ll call it, and while it’s still not as durable as we’d like, it’s a lot better. Though we’d recommend a frame wrap, of course, we’d recommend that on any bike, so maybe not a surprise there. If you stop, look closely and examine the details of this bike, it does look very nice, has quality bits, nice hardware and a very classy overall appearance. Trek have done a nice job making this a drool-inducing bike.

The Wolf’s Last Word

Price: $9,399 Weight: 36.4lbs Website: Trekbikes.com

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Trek Slash 8 Gen 6 review | Enduro Bike of the Year contender

Trek’s high-pivot, big-travel Slash 8 boasts good value and promises a lot on the trail

Laurence Crossman-Emms / Our Media

Robin Weaver

Composed feel at speed; climbs really well; great geometry; shock tunes helps it feel lively and playful; solid spec for the money

Tyres struggle in mud and aren’t tough enough; fork requires careful tuning to compensate for performance limitations

Trek has historically done well in our Enduro Bike of the Year category, with the Slash taking top honours back in 2021.

The latest Slash Gen 6 frames feature a high-pivot suspension design to deliver the 170mm of rear-wheel travel, come with a mixed-wheel setup as standard and offer up plenty of suspension and geometry adjustment.

On top of that, the new Slash also gets the standard lower, longer and slacker treatment in a bid to make this a genuine World enduro race winner.

The Slash 8 is the cheapest of the seven-bike Gen 6 line-up, uses an aluminium frame and comes with some solid parts from the likes of Shimano and Fox.

Although it's the cheapest of the eight bikes in my Enduro Bike of the Year test, it really packs a punch on the trail, with a ride that stands out for all the right reasons.

It’s sprightlier than expected and more playful too, but get stuck into the really rough stuff and it’s impressive just how well the rear end smooths out the trail.

Push too hard, though, and some of the spec choices start to hold this otherwise impressive rig back.

Trek Slash 8 Gen 6 frame and suspension details

The Slash 8 Gen 6 is made from Trek’s Alpha Platinum Aluminium, sports a plethora of rubberised driveside frame protection to help quieten chain slap and has under-belly guards to fend off rock strikes.

High-pivot designs are nothing new to Trek (the Diesel downhill bike was released more than 20 years ago), though they tend not to feature on bikes that need to be pedalled a lot.

That’s all changed with the latest Slash Gen 6 frame, which – you guessed it – now sports a high main pivot.

The bike continues to use Trek’s ABP (Active Braking Pivot) suspension layout, which sees the chain and seatstay pivot concentric to the rear wheel axle. That equates to a single pivot with a linkage-actuated rear shock.

The high main pivot creates a rearward axle path, designed to deal better with momentum killing square-edge hits.

In total, Trek says this moves a maximum of 18mm back from its starting point (growing the effective chainstay measurement) at around 135mm into the 170mm of rear-wheel travel before continuing to arc upwards and forwards for the remainder.

With 30 per cent sag, it’s estimated that the effective chainstay length will have increased by 11mm, sitting at around 440mm.

A massive upper idler helps to mitigate pedal kickback – a result of the rearward axle movement.

The lower idler cog is designed to take tension off the rear derailleur. This is not only to help it continue to shift properly and more efficiently, but to increase suspension sensitivity (because the lower section of the chain isn’t trying to extend the derailleur against its clutch mechanism).

Sizes small through to large need a standard 126-link chain, while the XL requires an extra-long 128-link chain.

To ensure the Slash Gen 6 can work with a coil-sprung shock , there’s a flip chip in the lower shock mount that enables you to increase the level of progression across the 170mm of travel from 20 to 25 per cent.

There’s also some integrated down tube storage for stashing essentials out of the way.

Trek Slash 8 Gen 6 geometry details

Trek offers the Slash Gen 6 in small, medium, medium/large, large and extra-large sizes.

The size small comes with 27.5in wheel front and back, while all other sizes use a 29in front and 27.5in rear wheel as standard.

There’s the option to switch to a larger rear wheel, although you’ll need to purchase a different lower shock mount to do so (£29.99).

Likewise, if you’re keen on altering the head angle, Trek sells aftermarket angled headset cups (plus or minus 1 degree) for £27.49.

I measured the Slash 8 to sport a slack head angle of 63.4 degrees, with a front centre of 790mm.

The seat tube angle is steep at 77.7 degrees, and the effective top tube quite compact for a size medium at 578mm.

Reach isn’t the longest at 448mm, but thanks to the compact seat tube lengths (400mm on the medium) across the size range, many riders will be able to size up if they’re looking for a roomier ride.

On paper, the Slash’s chainstay length looks really short at 429mm, but remember, as the bike drops through its travel, the rear axle moves backwards, effectively increasing this figure.

Trek Slash 8 Gen 6 specification

Trek has been smart with where it has spent the budget on the Slash 8.

Shimano XT gearing is great to see on this level of bike, and it’s no issue that this has been made possible in part thanks to the use of the lower-spec Deore crankset.

The brakes are also from Shimano, in the shape of Deore M6100 levers and four-piston M6120 calipers.

Taking care of the 170mm of travel at the front is a Fox 36 Rhythm fork, which uses the brand’s cheapest and most simplistic GRIP damper with limited adjustment compared to the pricier GRIP2 equivalent found on more expensive mountain bike forks .

This is matched to a Float X Performance rear shock.

In-house parts brand, Bontrager takes care of just about everything else, including the bar and stem. Unlike the pricier Slash 9.9 X0 AXS T-Type , it doesn’t use Trek's one-piece bar and stem, which is a plus in my eyes.

Bontrager also provides the wheels and XR5 Team Issue tyres.

All in, the medium Slash 8 Gen 6 on test weighed 17.01kg without pedals.

Trek Slash 8 Gen 6 ride impressions

I tested the Slash 8 on a wide variety of trails dotted around the Forest of Dean, South Wales and BikePark Wales.

These spanned from flowy jump lines through to hand-cut, steep, technical, natural descents, along with plenty of high-speed, rough-and-ready bike park tracks thrown in for good measure.

This enabled me to develop a thorough understanding of what the Slash 8 is good at and where it struggles.

Trek Slash 8 Gen 6 setup

Setup was quite straightforward, settling on 30 per cent sag for my 68kg weight with 147psi in the spring and the rebound damping left fully open. However, the fork became more of a puzzle as time progressed.

Initially, I settled on 71psi in the fork’s air spring, with only a couple of clicks of rebound damping wound on (from fully open). This offered masses of comfort and a decent level of traction.

As time went by and I felt more comfortable on the Trek, I had to increase the spring pressure and rebound damping to try to raise the level of support on offer.

I finished with 75.5psi in the air spring and no volume spacers.

Trek Slash 8 Gen 6 climbing performance

The Trek’s seated position is upright and comfortable, thanks to the steep seat tube angle.

It’s not particularly stretched out, though, due to the relatively short effective top tube and stumpy 35mm stem.

I wasn’t ever uncomfortable and didn’t feel cramped, but I noticed that compact position occasionally when scaling steeper, technical inclines. At 172cm, I think I could comfortably go up a frame size and negate these issues, though.

However, that’s not the headline here. What takes all the attention is how well this long-travel big hitter pedals.

Get cranking and the rear shock stays spookily still while you tick off the vertical metres. It helps that the tyres roll pretty quickly, too, limiting drag and injecting a bit of get up and go into proceedings.

With so little movement from the back end, you can leave the shock’s low-speed compression lever well alone because you don’t need it.

On every climb I tried, the Slash 8 felt the sprightliest and most energetic when pointed uphill, which is quite surprising considering its weight. It’s only when faced with soft mud that progress is stifled, due to the rear tyre lacking enough bite to generate grip and spinning up easier than others.

Trek Slash 8 Gen 6 descending performance

That energetic feel translates instantly to the trail when descending, too.

Trek has nailed the rear shock tune with this bike, producing a seriously capable bump gulper that helps generate traction when needed, but never sucks the fun out of even the tamest of tracks.

The fast-rolling tyres play a part in all of this, but the comfortable, well-balanced suspension helps the Slash remain playful, agile and, most importantly, fun when skimming through undulations and gapping rollers.

Speed seems to come easily, even when boosting in and out of slow-paced turns. Pick-up from the rear hub is quick and dumping gears quickly thanks to the precise XT shifter and derailleur is rapid when you find yourself wanting to inject even more speed to proceedings.

Square-edge what?

Pummel into faster, rougher sections of trail and the back end of the Slash really starts to shine.

The high-pivot design does a great job of scalping the peaks of the ugliest square-edge hits, helping you to stay online and composed at speed.

It’s this sensation that builds confidence and encourages you to ride faster. However, this is when you’ll start to reach the limits of the fork and tyres.

The Fox 36 Rhythm fork, with its GRIP damper, is one of the comfiest suspension forks on the market. But push it hard and you’ll be left puzzling over how to best balance that comfort with support.

My initial starting point delivered a beautifully supple ride, but lacked support when riding faster tracks, causing the front end to drop away with higher-load compressions and landings, and upsetting overall balance.

Upping the spring pressure and adding volume spacers helps here, but reduces overall comfort. The basic compression dial doesn’t exactly enable fine-tuning.

To unlock the full potential of the Slash 8, you’d be best to get the fork professionally tuned (roughly £120 for a service, plus £50 for custom tuning) so it can better handle being ridden hard without compromising that impressive comfort too much.

Similarly, I found myself incrementally adding pressure to the tyres , too, because they’re not as supportive or as tough as the best mountain bike tyres . This was largely because I found myself burping the rear tyre all too easily.

Thanks to the supple suspension, I didn’t find this to impact comfort too much, but you can feel the effects in terms of traction, especially when tackling anything remotely wet.

Swapping to your preferred tyre combo from the get-go should be high on your to-do list. You might want to ditch the chunky, wide-diameter grips while you’re at it.

Mega momentum

Despite those niggles, I never failed to have fun riding the Slash 8 and was always impressed by how well it could maintain speed.

On rough, high-speed tracks littered with rocks ready to sap your speed, the Trek always managed to retain incredible pace.

The back end beavers away tirelessly to isolate you from the worst impacts, enabling you to remain centred on the bike and focused on your line.

When speed started to dwindle, I had sufficient support, enabling me to pump undulations and compression in a bid to boost speed. However, I’d argue the Slash isn’t as direct and punchy in that sense as some of its rivals.

The geometry isn’t as lengthy or as raked out as some, but it still feels a confident bike to ride, even more so if you swap to grippier tyres.

Through the turns, the low 340mm bottom bracket helps to keep things suitably stable, while the suspension tracks the terrain almost effortlessly.

How does the Trek Slash 8 Gen 6 compare?

As the second most expensive bike within the Enduro Bike of the Year test, I’m going to compare the Slash 8 to the Transition Spire Alloy NX.

The Spire costs £50 more and comes with the same rear shock and a Marzocchi Z1 fork with the same GRIP damper.

But while the Slash features pricier Shimano XT gearing, the Spire has SRAM’s NX Eagle transmission. This proved to be clunkier and more problematic to keep running smoothly after months of riding in grim conditions.

The Spire suffers from the same fork issues as the Slash – impressive comfort but lacking in high-speed support when you really start pushing the bike.

Both bikes climb well, but the Slash feels a little punchier when grinding its way uphill.

On the descents, while the Spire offers a smooth ride, it can’t quite compete with the supple high-pivot bump-eating back end of the Slash.

The Slash is, overall, a comfier ride, too, with more feedback coming through the front end of the Spire when battering through repeated hits.

Enduro Bike of the Year 2024 | How we tested

The expectations resting on the shoulders of any enduro bike couldn’t be heavier. Creating a bike capable of tackling just about any trail revolves around smart choices and compromise.

In the simplest terms, enduro riding and racing is all about winching your way up to the top of a hill or mountain, then tackling an often-challenging descent.

These bikes are designed to excel at downhills.

How a bike handles the climb isn’t the be-all and end-all when it comes to overall performance, but pedalling efficiency and seated geometry still need to be factored in.

When it comes to geometry, we’re looking for stability and composure, but without dulling playfulness and agility.

A balanced suspension system creates a stable ride, but engineers also need to factor in the right amount of support for the rider to push against when pumping the terrain, and enough sensitivity to ensure the tyres can maximise traction on just about any surface.

Over a three-month period, all the bikes in this category were ridden back-to-back, as well as in different orders, in a bid to eke out every difference between them.

The trails in question varied from steep, natural downhill tracks and forest singletrack through to the high speeds and hefty impacts of BikePark Wales.

Our Enduro Bike of the Year contenders

• Santa Cruz Megatower C R
• Transition Spire Alloy NX
• Ibis HD6 XT
• Kona Process X CR
• Marin Alpine Trail XR
• YT Capra 29 Core 4
• Cube Stereo One77 C:68X TM 29
• Trek Slash 8 Gen 6

Trek Slash 8 Gen 6 bottom line

The Trek is a seriously smooth operator and really impressive for the cash.

Supple, well-balanced suspension and some really solid gear choices make it a formidable bike on the hills.

The fact that it has so much travel and a high-pivot, but climbs like a much lighter, shorter-travel machine is a massive bonus.

Push hard and the fork can’t keep up with the shock – and lacks the same level of composure at really high speeds. Meanwhile, the tyres are best suited to trail-centre pootling rather than full-on enduro riding and racing.

Swap the tyres and get the fork tuned to optimise performance and the Slash 8 Gen 6 will be an absolute rocket ship on the toughest of trails.

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Trek Slash Review | A totally one-of-a-kind custom bike build

The not-so-minor details.

Trek Slash 8

Trek Bicycles Australia

https://www.trekbikes.com

$3,312 AUD (frame only)

Last year saw Trek pull the wrappers off of its all-new Slash enduro bike. Featuring a redesigned chassis with in-built downtube storage, the 2021 Trek Slash received a whole suite of updates, including a brand new rear shock that was codeveloped alongside RockShox. Our two testers, Ben & Dan, were thoroughly impressed with the supple suspension and the bike’s ability to monster-truck its way through horrendously rocky and technical terrain. However, it was the Slash’s agility that was the real surprise, giving it an approachable and easy-to-manage demeanour on less gnarly singletrack. Despite its EWS-level capabilities, the Slash is a proper all-rounder.

The bike we tested prior to the official launch was the top-end Slash 9.9 X01. However, Trek offers three other models beneath it, with the Slash 7 being the cheapest option at $4,999 AUD. For those who want to build something a little different, there’s also the option to buy the Slash frameset.

And that’s exactly what Ben decided to do.

Going Off-Script With The Trek Slash

But first, allow us to introduce you to our fellow Flow Frother.

Ben is a full-time bike shop guru, a skilled mechanic, and an appreciator of very robust IIPAs. With some three decades of riding and bike industry experience behind him, he’s also a talented and discerning rider, with an infectious enthusiasm for geeking out on new bike tech, while simultaneously being a connoisseur of fine retro collectables. Notable highlights in the shed include a Klein Mantra, Shimano Airlines groupset and a Manitou X-Vert Carbon. Not that Mick is jealous or anything.

After being thoroughly impressed with the Slash 9.9 X01, Ben heard through the grapevine that Trek Australia would be bringing in a very limited number of Slash framesets into the country. One impulse-purchase later, and a Slash 8 frame was on order.

To assemble his custom Slash, Ben’s chosen an eclectic build kit that is comprised of a variety of components that he’s been testing for Flow, along with a few parts that were purchased specifically for this bike. The build hasn’t stayed still either – a number of components have already been swapped around in search of the perfect setup, and there are a few upgrades planned for the future too.

Without further ado, let’s get stuck into the build and Ben’s impressions of this one-of-a-kind Trek Slash and some of the parts strapped to it.

The heart of any bike is the frame, so let’s start there Ben. Why did you go for the Slash?

Well I had been hankering after a big bike for a while after many years of riding XC and trail bikes. I used to ride and race a lot of DH in my younger days and have never quite been able to let it go! The Slash just had this great mix of playfulness and agility, whilst also being able to just steamroll through techy sections and feel very planted and confidence inspiring. It’s super fun to ride.

I opted for a frame only option as by the time I had decided to order one, only a few days after the official release, the complete bikes had already been snapped up! Lead times on the second shipment of complete bikes was far too long for my impatient nature so I sourced a frame before they all disappeared.

Did you choose the alloy frame specifically over the carbon option?

I never really considered the carbon option as I wanted a bike that I could be less delicate with and worry less about when tackling the extremely rocky local trails we have here. The added weight didn’t phase me, I have other bikes that are light and fast uphill, and that’s not what I bought the Slash for. The alloy Slash 8 frame (and complete bike) are perhaps the sweet spot in the Slash line up as it shares the same Rockshox Super Deluxe Ultimate Thru Shaft shock that you’ll find on the more posh carbon 9.8 and 9.9 models. This shock is a big part of why the Slash handles as well as it does, so it’s cool to see it offered on the alloy frame as quite often alloy models receive a more basic shock.

The alloy frame sells for nearly half of the carbon frame option with the same shock.

As with the carbon frames, the alloy Slash still gets the new downtube storage accessed by a trapdoor under the bottle cage, adjustable geometry via the Mino Link and generous downtube protection. Price was also a consideration. I already own a… ahem …not insignificant amount of expensive bikes so there wasn’t much scope for a full on enduro dream machine. The alloy frame sells for nearly half of the carbon frame option with the same shock. I’m never going to be at the pointy end of an enduro race so the alloy option was a bit of a no brainer.

That Trust fork is absolutely bonkers! Why the heck is that on there?

Ah, yes, the elephant in the room! The Shout is the second fork from the now COVID coma-induced Trust Performance. Trust was founded by three industry veterans, most notably the hugely influential Dave Weagle. Both Trust fork models, the 130mm Message and the 178mm Shout are linkage driven forks made almost entirely of carbon fibre and feature an air spring in each leg and a three-position damper unit in one leg.

Linkage driven forks are nothing new but these are perhaps the first to really benefit from the engineering flexibility of modern carbon fibre, while adding in intricately adjustable dampers and air springs.

I really feel the Trust forks are one of those products that, whilst not perfect, has perhaps paved the way for others to try something different.

I actually didn’t intend on building the Slash with the Trust Shout fork to begin with. I had a perfectly nice set of Lyrik Ultimates ready to go but the Trust came up for sale on the second hand market just as I was finishing the build, and I couldn’t say no! I have the shorter travel Trust Message fork on another bike and love it, so I was really keen to see how the 178mm Shout fork would feel.

I’m drawn to the more outlandish bicycle and component designs as these are what can push the envelope of what we currently ride and the way we think about bike and component design. I think that’s one of the reasons I have such a love for vintage mountain bikes. There was so much experimentation back in the day and lack of concern about what company shareholders would think. Don’t get me wrong, there were a lot of mis-steps but they have all in some way shaped the pretty amazing mountain bike and parts we ride now. I really feel the Trust forks are one of those products that, whilst not perfect, has perhaps paved the way for others to try something different.

You’ve since fitted a more conventional telescopic fork. How’s the performance in comparison?

Yeah I’ve now fitted a 170mm 2020 Lyrik Ultimate upgraded with the new C1 Debonair spring . It has really changed the way the bike behaves in a number of ways.

Instantly noticeable was the improvement in small bump sensitivity, particularly on very rocky, slower sections of trail, both uphill and downhill. The main weakness of the Trust fork was its climbing performance, admittedly not the designers’ biggest concern when making the fork but worth mentioning. The Trust fork tends to sit really high in its travel, raising the front of the bike and making slow, technical, rock-strewn climbs particularly tough going. The Lyrik is much plusher off the top, which naturally tends to lower the front end as you shift your weight forward. The initial suppleness also does a better job of soaking up momentum robbing rocks that can be the difference between cleaning a tech climb or not.

The difference between the forks when the terrain points down is interesting. I felt the Trust shines on high speed flow trails, where the stiffness and lateral rigidity of the huge carbon legs allows you to corner and carry speed in a way that makes you feel as though you could give Greg Minnaar a run for his money! The Lyrik still feels great in comparison on this type of descent but doesn’t quite give you the confidence to really let go on the corners like the Trust does.

When the descents become more technical and rocky the Trust does not feel as composed as the Lyrik, there is definitely a lot more feedback through the bars. The Lyrik does a better job of smoothing out the trail but the Trust feels faster and as though it carries more momentum. The rearward axle path of the Trust’s initial stroke has a lot to do with this as the wheel can more quickly move out of the way of an incoming rock, minimising its effect on your forward motion. It will be interesting to go back to the Trust after some time on the Lyrik to see if it highlights any other differences.

Let’s talk about the Crank Brothers Synthesis Alloy wheels; how have those held up?

Yeah, I’ve been testing out the entry level Crank Brothers Synthesis Alloy Enduro wheels, which sell for a reasonable $945 AUD and weigh in at 2,130g for the pair. Like the carbon versions, these wheels are designed and built differently front and rear to provide different ride qualities.

The front rim is 31.5mm internally compared to 29.5mm for the rear, the front also has 28 spokes where the rear has 32. Crank Brothers reckons the wider rim profile better supports a wider front tyre for cornering stability whilst also rounding the tyre’s profile, which again can help in the corners. The lower spoke count theoretically reduces front wheel stiffness a touch, potentially allowing a touch more compliance through choppy corners where an overly stiff front wheel can ping off rocks and ruts and leave you feeling sketchy.

The narrower rear rim is meant to better match up with a narrower, faster rolling rear tyre. The 32 spokes provide a laterally stiffer wheel, allowing more precise tracking through the corners.

It’s especially noticeable on technical climbs, I found myself second guessing every pedal stroke when trying to pick a line over rocky climbs.

The wheels have held up pretty well, suffering only a minor ding to the rear rim. This is no slight on the rims though, our trails are very rocky and I’m sure any alloy rim would have sustained some damage. Overall the wheels felt fine, not too flexy, not too stiff. This could be down to the difference in stiffness Crank Brothers reckon it has designed into the wheels, but this is hard to quantify.

The major issue for me with these wheels is the sluggish engagement of the rear hub. It’s 17 degrees, which is very slow, and I reckon for a nearly a $1000 wheelset these days is unforgivable. It’s especially noticeable on technical climbs, I found myself second guessing every pedal stroke when trying to pick a line over rocky climbs.

On the plus side the wheels are built with readily available J-bend spokes, external nipples and easily sourced cartridge bearings meaning they will be easy to maintain and live with. However, replacement rims aren’t particularly cheap at $195 AUD each. This is definitely worth factoring in if you are a frequent rim muncher.

My overall verdict on the Synthesis Enduro alloy is that they could really benefit from a higher-engaging freehub to be competitive with other wheels out there at this price point, or they need to come down in price. Whilst the differing ride qualities built into the front and rear is a nice concept, I personally haven’t found the benefits noticeable enough on the trail to justify the price or overcome the drawbacks of the rear hub.

Now you’re on the carbon Bontrager Line Pro 30 wheels. How do they compare?

After riding the Synthesis wheels, I then fitted a set of Bontrager Line Pro 30s. These sell for considerably more at $1,999 AUD, but they’re also lighter at 1,881g for the set, including rim strips and valves (you can get the full tech rundown on these wheels in our separate tech feature here ).

When I swapped wheels, I kept the same tyres and overall setup for the whole bike, in order to isolate the performance differences as accurately as possible. And in comparison, they feel great, lighter and more direct on the trail. They are 250 grams lighter than the Crank Brothers wheels, which doesn’t sound like a lot but it is definitely noticeable. The carbon rims add to the feeling of directness, without feeling harsh or chattery like some carbon wheels can (like previous generation Bontrager carbon wheels).

The rear hub features the Rapid Drive 108 freehub mechanism, which offers 3.3 degrees of engagement. This is super fast, especially when compared to the 17 degrees on offer from the Crank Brothers wheels.

Bontrager claims that the rims found on the new Line Pro 30s are the strongest it has ever tested . We’ll have to take this with a grain of salt as testing is obviously done in house. Bontrager does back all of its carbon wheels with a lifetime warranty and a 2 year “ no questions asked ” crash replacement policy though. Damage your carbon wheels within a 2 year period and Bontrager will replace them. This is increasingly common in the carbon wheel market these days but still pretty cool to have that peace of mind when purchasing.

Would you recommend either wheelset over the other?

I prefer the Bontrager wheels over the Crank Brothers but they are twice the price, so it’s not a fair comparison. I personally love the direct and lively feel of a stiff carbon wheelset. These qualities worked well with the Slash’s super supple rear suspension as the wheels could handle the speed I found myself entering with into chunky rock gardens and off-camber sections.

By comparison the Crank Brothers wheels didn’t feel as positive or stiff. This could actually be a good thing though, particularly for lighter riders or those on hardtails who are looking for a bit more compliance from their wheels. I’d personally like to see a quicker-engaging freehub, but if you’re not so bothered by that, they’re a solid set of hoops for under a grand.

It’s worth mentioning the Bontrager wheelset that sits below the Line Pro 30, the Line Elite 30. These wheels are $1,499 AUD and feature the same Rapid Drive 108 hub internals and the same warranty support, but are built with slightly heavier carbon rims and J-Bend spokes. The Line Elite wheels are only 130 grams heavier, and in my mind would be worth considering when looking for an off-the-shelf wheelset.

What tyres are you currently using?

I’ve been running a Maxxis Minion DHF EXO 2.5in up front and a Maxxis Dissector EXO+ 2.4in on the rear, both with the 3C Maxx Terra rubber compound. The Minion DHF weighs in at 1,065 grams, but while the Dissector is meant to have a heavier duty EXO+ casing, it’s actually quite a bit lighter at 925 grams.

The Minion DHF, as we all know, is superb and provides a ton of confidence up front. The Dissector certainly rolls well for an aggressive tyre but hasn’t given me the confidence that the Minion did. The Dissector did also suffer a ride-ending pinch-flat after sustaining a big hole on the bead and through the top of the casing. I’m not hard on tyres so this was a bit disappointing. If you’re a certified tyre shredder then consider the tougher Double Down casing, particularly on the rear tyre. That’s exactly what I’ll be ordering shortly!

You’ve been testing the Shimano Deore 1×12 drivetrain too. Give us the lowdown on your experience so far.

Listen up bike snobs (myself included) – Shimano Deore 12 speed is bloody amazing, seriously impressive! The shift quality is superb, particularly when shifting into harder gears as it uses the same HG+ cassette design as SLX, XT and XTR 12 speed groupsets. I ride the XTR 12 speed groupset on my XC bike and honestly the difference between this and the Deore groupset is so small. The shifter feels a touch softer and a little less positive than XTR but the actual difference in shift quality is negligible.

I do miss the multiple upshift offered by XT and XTR shifters but if you’ve never ridden with this it won’t be an issue. It has not given me a mis-shift or any cause for concern since it’s been fitted to the Slash, its performance is outstanding, especially considering the cost of the entire groupset is less than the cost of a cassette from a top-tier groupset from either Shimano or SRAM.

I think in the long term I would consider upgrading the cranks and the cassette as these components are pretty heavy. Changing to XT cranks and cassette for example would save nearly 300 grams without sacrificing any strength or durability (for confirmed weights and a closer look at the full Deore M6100 groupset, check out our detailed tech feature here ).

What about the Deore M6120 brakes?

The Deore four-piston brakes have been impressive with good power and modulation. Fitting and set up is simple and straightforward, and the bleed process is the same as all current Shimano models. I’ve paired them with Shimano XT Ice Tech 180mm rotors front and rear.

Modulation on Shimano’s four-piston brakes is improved over their less powerful two-piston models, and there’s a really nice power progression as you move through the lever stroke. The lever feel was consistent throughout the test, with none of the wandering bite point that some Shimano models have had a problem with.

I will say that the stock resin pads didn’t quite give the bite that and power that I was used to from sintered metal pads though. Unfortunately I couldn’t find anywhere that had stock of sintered Shimano pads to suit these Deore callipers, and it’s worth noting that the finned pads for the four-piston XT and SLX brakes are not compatible with these Deore callipers.

One of our main suppliers at the shop had just started doing Galfer pads and rotors so I’ve since fitted a pair of the standard compound pads, which made a big difference to braking power and firmed up the lever feel at the bite point. For anyone with Shimano brakes who’s looking for more power over the stock resin brake pads, I can highly recommend upgrading to some sintered or semi-metallic pads.

Tell us about the rest of your bike’s cockpit setup.

I’m running a 45mm long Bontrager stem, which clamps a 35mm One Up carbon bar with 20mm of rise. I’ve cut these down from 800mm to 780mm. Currently I’m riding the ODI Elite Flow grips and a 180mm travel OneUp dropper, which is paired to the Shimano dropper lever.

The OneUp bar is super comfortable due to its flattened, oval shape that allows some vertical flex whilst still retaining fore and aft stiffness. They are a huge improvement over the PRO Tharsis carbon bars I initially built the bike with, those things are really stiff, and I found them to be quite harsh.

The dropper has also been top-notch, though I’m not in love with the Shimano lever. It works fine, and the textured paddle is nice, though the return spring requires more thumb force every time you press the paddle, and the physical position of the paddle is too close to the grips. Some further adjustability, or just a bit more clearance between the paddle and the grip would be nice.

What do you love most about it?

As I mentioned before, the bike’s ability to feel lively, and chuckable whilst still feeling planted and stable when needed, is a great quality. The rear shock and shock tune is superb as well, really smooth and supple at the top off the top, supportive in the mid stroke and ramps up nicely at the end of the travel.

I also really like the Knock Block steering limiter, which has been essential in previous generations to stop the fork crown slamming into the downtube. With the new Slash, this is no longer needed but it still prevents brakes and shifters whacking your top tube in a crash. This also allows you to run nice tidy cables and brake hoses without worrying about them getting damaged in a crash when the bars try to fully rotate. The turning radius on the Knock Block has been increased over the previous generation, it also comes with a replacement chip to allow for complete removal, if you feel like trying to channel your inner Brandon Semenuk!

Any other changes on the horizon?

I’d like to try and squeeze a 200-210mm travel dropper post in there if possible, just to get the saddle more out of the way on some of the really steep sections. To help minimise rock strikes I’ll probably switch to 170mm crank arms. Only the 175mm arms were available at the time of launch, and while they haven’t been a huge issue, any reduction in your pedals smacking into rocks is a plus. I’ll probably switch to a Wolf Tooth dropper remote at some stage too.

In the longer term I’d love to give the Vorsprung Secus a go on the Lyrik Ultimate. The Secus is essentially an enlarged negative air spring that actually sits outside of the fork at the base of the lower leg. It’s supposed to give your air fork a “ coil like feel” in the top 2/3rd of the travel whilst providing a more gentle ramp up at the end of the travel.

The only other more immediate change will be an Absolute Black oval chainring, as I bloody love those things. I’ve used them for years now on almost every bike I own, I find they really help smooth out power delivery on steep, loose pinches, which helps prevent a loss of traction at a critical moment. I’ve ridden them for so long that normal round rings feel a bit weird!

Ben’s Custom Trek Slash 8 Specs

• Frame |  Alpha Platinum Alloy, ABP Suspension Design, 160mm Travel
• Fork | RockShox Lyrik Ultimate, Charger RC2 Damper, 42mm Offset, 170mm Travel
• Shock |  RockShox Super Deluxe Ultimate, Thru-Shaft 3-Position Damper, 230×62.5mm
• Wheels | Bontrager Line Pro 30, Carbon Rims, 30mm Inner Width
• Tyres | Maxxis Minion DHF 3C Maxx Terra 2.5WT Front & Dissector EXO+ 3C Maxx Terra 2.4WT Rear
• Drivetrain | Shimano Deore 1×12 w/Deore 32T Crankset & 10-51T Cassette
• Brakes | Shimano Deore 4-Piston w/180mm Rotors
• Bar | OneUp Carbon, 35mm Diameter, 20mm Rise, 780mm Wide
• Stem | Bontrager Line, Knock Block, 45mm Length
• Grips | ODI Elite Flow Lock-On
• Seatpost | OneUP Dropper, 34.9mm Diameter, 180mm Travel
• Saddle | Bontrager Kovee Elite
• Size Tested | Large
• Confirmed Weight | 15.75kg (without pedals)
• RRP | $3,312 AUD (Frame & Shock)

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New 2024 Trek Slash 9.9 XO AXS first ride review – A new evolutionary stage of high pivot bikes?

The new 2024 Trek Slash is right on trend: high pivot rear suspension, mullet wheel set-up, generous amounts of travel and plenty of adjustment options. Furthermore, it combines both familiar and newly developed features that are meant to simplify your riding experience. After six weeks of testing on both sides of the pond, we were able to gather countless impressions, both good and not so good.

The Slash has been an integral part of Trek’s portfolio for over 10 years, and is now entering its 6th generation. The most significant innovation is the new rear suspension, which relies on a high pivot design and generates a very generous amount of travel, bringing the Slash in line with the latest generation of enduro bikes. Up until now, Trek have only used the high pivot system on their downhill bike, the Session, which nevertheless allowed them to gather lots of practical experience with the system and use their World Cup riders’ feedback to develop the new enduro rig. The new Slash generates 170 mm of travel both front and rear, and rolls out of the factory sporting a mullet. An interchangeable shock mount, however, allows you to convert it to a full 29er. As usual, Trek are releasing both an alloy and a carbon version of the new Slash, both of which are available in several different spec variants. We’ve already put the new Trek Slash 9.9 XO AXS 2024 through the wringer over a 6 month period, dipping its tires both into Canadian and European soil to gather some exciting insights.

The detail solutions of the new 2024 Trek Slash

The predecessor of the 2024 Trek Slash already came with a practical storage compartment integrated into the down tube, which Trek has updated for the latest Slash iteration. The opening is much bigger, making it easier to reach all the trail essentials you store inside it. Moreover, the edges of the compartment are still framed with a plastic liner, preventing you from cutting your fingers or damaging the contents when you pull them out of the compartment. The alloy frame has a storage compartment too and all models come standard with a small pouch for all your trail essentials, which can be easily pulled out of the frame using the bright red Cordura tab. The closure system relies on a simple lever that disappears under the bottle cage when engaged, and is easy to operate even while wearing gloves. The cables of the new Slash are routed internally and only reappear briefly at the transition from the main frame and swingarm. The cable ports are in a rather unusual position, sitting prominently on the front of the head tube – this look takes some getting used to! In combination with a wireless drivetrain, Trek close the cable ports with small rubber plugs.

There’s an additional tool mount underneath the top tube, which allows you to carry a spare inner tube or a tool strap, for example. In typical Trek fashion, the new Session comes standard with an integrated Bontrager BITS mini tool in the steerer tube, which includes all of the basic tools required for essential trailside repairs. That said, removing the tool from the steerer tube requires strong fingers and, as usual, the lever of the closing mechanism rattles on the trail. Trek also hide a 6 mm Allen key in the rear thru-axle.

For model year 2024, Trek provided the Slash with several protective features, all of which are meant to preserve the bike’s value. Amongst them is the generously sized integrated mudguard, which is bolted directly to the seat stay and is meant to protect the seat tube from stray rocks. Unfortunately, this has to be removed if you want to swap the 27.5” rear wheel for a bigger 29″ rear wheel. Furthermore, the down tube comes standard with a pair of dual-density TPU plates, which allow you to replace the inner section if it gets damaged. In addition, the frame comes with an additional protective layer under the final finish. Trek also redeveloped the chainstay protector from the ground up, raising both the inner and outer edges to prevent chain slap more effectively – and this really works, ensuring a quiet ride on the trail.

The high-pivot rear suspension of the new 2024 Trek Slash

While the new 2024 Trek Slash 2024 still relies on the same linkage-driven single pivot rear suspension, it combines it with a high pivot point design. This positions the main pivot point well above the chainring, allowing the rear wheel to swing up and backwards during an impact. This rearward axle path can help to make the suspension feel smoother over square-edged hits, ironing out roots and rocks more efficiently. However, the system also has its drawbacks: as the axle moves rearwards through the travel, the distance between the cassette and chainring grows, resulting in wheelbase and chainstay growth. This pulls the chain backwards, manifesting in high levels of pedal kickback and resulting in an imbalanced weight distribution of the rider on the bike throughout the travel. To counteract this, a chain idler pulley is fitted on the seat tube, which helps minimise pedal kickback and also gives high-pivot bikes their characteristic look. This also allows the engineers to fine tune the bike’s anti-squat and anti-rise levels independently simply by moving the position of the idler pulley. The unusually big 19T idler pulley is meant to mitigate the negative effect that the high pivot system has on pedalling efficiency, because the bigger pulley has a wider radius. Furthermore, Trek use a small chain guide to prevent the chain from falling off the idler.

The new 2024 Slash also features an additional pulley below the chainstay, which isn’t that common with high pivot bikes. This special pulley also includes an MRP bash guard and can be retrofitted to other high pivot bikes. Its job is to prevent the chain from stretching under the chainstay and thus to stop it from pulling on the rear derailleur. That said, even with the biggest XL frame, the chain runs at a sharp angle in the lowest gears, as the distance between the rear derailleur cage and the idler pulley is very small. While this didn’t cause us any problems on the trail, we’re not sure how good this is, both for pedalling efficiency and the chain’s service life. Speaking of the chain, with all frame sizes up to L, you’ll get away with a conventional 126-link chain. The new Slash in XL, however, requires 128 links, meaning that you need two chains.

The new 2024 Slash still relies on Trek’s proprietary Active Breaking Pivot or ABP technology, which can be found on most of their full suspension bikes and is designed to keep the rear suspension active even under heavy braking, helping to maintain traction.

The spec of our test bike – The Trek 2024 Slash 9.9 XO AXS

Our Trek Slash test bike comes equipped with Rockshox Ultimate suspension consisting of a 170 mm ZEB Charger 3.0 fork with independently adjustable low- and high-speed compression damping, and a brand- new Vivid Ultimate air shock , which offers externally adjustable compression and rebound settings as well as a climb switch. Unlike the Super Deluxe, the new Vivid relies on a high-volume air chamber and Rockshox’s new proprietary Touchdown damper. Unlike the rest of the Trek range, the Slash doesn’t use a Thru Shaft damper, which comes standard with most of their full-suspension bikes and is developed specifically for Trek.

As the name extension suggests, the 2024 Trek Slash 9.9 XO AXS employs a new electronic SRAM X0 Eagle Transmission drivetrain. The rear derailleur mounts directly to the thru-axle and worked flawlessly throughout our test. SRAM also supply the wireless, electronic Reverb AXS dropper post, but this only offers a meagre 170 mm of travel, which is far too little for a modern enduro bike. However, there isn’t a longer-travel version of the Reverb AXS dropper, so we recommend swapping the standard dropper for a cable-operated model if needed. Given the seat tube’s generous insertion depth, you could even push a 240 mm OneUp Components V2 dropper post all the way into the frame of a Slash in size L. Needless to say, the brand-new drivetrain is complemented with SRAM’s four-piston Code Stealth Silver brakes, which, just like the old RSC model, feature tool-free lever reach and bite point adjustments as well as SRAM’s proprietary SwingLink lever for optimal modulation. Compared to the Stealth Ultimate flagship model, the Silver variant only forgoes the carbon levers, tipping the scales at just 8 g more. Due to the new design, the brake lines run parallel and close to the handlebars, which ensures a cleaner look but can cause the cables to rattle – this can be easily fixed with a couple of additional clamps or zip ties ;) The brakes are paired with 200 mm rotors front and rear, which suit the Slash’s character and field of application rather well! For more oomph, you can can upgrade to 220 mm rotors both front and rear, because both the frame and fork are approved for it.

For the rest of the spec, Trek rely on their in-house component brand Bontrager, including a Bontrager Line Pro 30 carbon wheelset, which didn’t survive the testing sessions unscathed, with several spokes snapping after just 3 weeks of deployment. In addition, the rims are paired with flimsy, puncture-prone tires, which force you to run higher air pressure to avoid burping and snake bites. We recommend upgrading the standard Bontrager SE6 and SE5 tires for more robust tires before you start riding. In this test, we swapped to tires with a tougher DH casing after just a few laps. For the cockpit, Trek rely on an 820 mm Bontrager RSL one-piece handlebar/stem unit, which might look fancy but doesn’t allow for fine tuning except for the stem height, which can be changed using spacers. On top of that, the handlebars are very stiff and get even stiffer if you shorten them, like we did! With such a potent enduro bike, an adjustable cockpit makes more sense because it allows you to adapt the front end ergonomics to your anatomy. With the standard spec, our 2024 Trek Slash 9.9 XO AXS test bike in size L tips the scales at 15.7 kg.

Trek Slash 9.9 X0 AXS 2024

Specifications.

Fork RockShox ZEB Ultimate 170 mm Rear Shock RockShox Vivid Ultimate 170 mm Seatpost RockShox Reverb AXS 170 mm Brakes SRAM CODE Silver 200/200 mm Drivetrain SRAM Eagle Transmission X0 1x12 Stem Bontrager RSL 35 mm Handlebar Bontrager RSL 820 mm Wheelset Bontrager Line Pro 30 29"/27.5" Tires Bontrager SE6 Team Issue/ Bontrager SE5 Team Issue 2.5"/2.4"

Technical Data

Size S M M/L L XL

Specific Features

storage compartment Flip Chip Toolmount

More spec variants of the 2024 Trek Slash

As already mentioned, the new 2024 Trek Slash is available both with an alloy and carbon frame. That said, none of the alloy versions comes with a high-end spec, meaning that you have to order the frame kit if you want to combine an aluminium frame with top-tier suspension, for example. Prices for complete builds range between € 4,499 and € 12,499, and the bikes should be already available from all official Trek dealers. The American manufacturer also lets you test ride their bikes in one of their “Test-a-Trek Centres”. Starting today, you can test the new Slash in Lenzerheide, Saalbach and Sölden.

The alloy version of the new Slash is available in two spec variants. The entry-level Slash 8 XT model comes equipped with a FOX 36 Rhythm fork and a hybrid Shimano XT/SLX drivetrain. Shimano also supply the four-piston Deore M6100 brakes. The Slash 9 GX relies on higher quality RockShox Select+ suspension and SRAM’s new electronic GX Transmission drivetrain, with matching SRAM Code Bronze four-piston brakes. The Slash 9.8 GX combines the same identical spec with a carbon frame.

The flagship Slash 9.9 XX model comes equipped with electronic RockShox Flight Attendant suspension, electronic SRAM XX Transmission drivetrain and wireless RockShox Reverb seatpost. The rest of the spec consists exclusively of top-tier components and plenty of carbon bling. However, all the fancy components come at a price – an eye watering € 12,499! However, Trek have released a total of 5 carbon variants, offering a suitable option for all sorts of wallets.

The geometry of the new 2024 Trek Slash

The new Trek Slash 2024 will be available in 5 sizes, S to XL, and there’s also an intermediate size called M/L. All models in size S feature a curved top tube and 27.5″ wheels front and rear. From size M onwards, the new Slash rolls on a mixed wheel setup with a 29″ wheel at the front and smaller 27.5″ wheel at the rear. However, from size M upwards you can also use a 29″ rear wheel using a different shock mount, but this has to be bought separately and isn’t included in the frameset. The optional shock mount comes with a flip chip that allows you to change the progression of the rear suspension from 20% to 25%, which is intended for coil shock conversions.

Trek deliver the new Slash with three different headset cups, which allow you to change the head angle by up to 1.5°. Of course, by altering the head angle you’ll also change the reach, bottom bracket height and stack height. The new Slash comes standard in the neutral setting. When swapping the cups, however, the lower one has to be installed with a bearing press, meaning that you can’t just quickly swap cups on the trailside. In the neutral setting, the Slash has a 63.3° head angle, which can be changed to either 62.6° or 64.1°. In addition, Trek forgo their usual Knock Block with the new Slash, which means that you don’t have a steering stop limiter.

The position of the bottom bracket allows engineers to achieve different chainstay lengths by using the same rear end, whereby sizes M/L and L share the same values. Simply put, all frame sizes share the same identical swingarm but rely on a slightly different bottom bracket position to allow for the size-specific effective chainstay length. The advantage of this system is that you can easily replace the rear end in case of damage.In size L, the Slash combines 488 mm reach with a short 435 mm seat tube, which offers a generous insertion depth for long-travel dropper posts. The seat tube is short across all sizes, ensuring sufficient freedom of movement on the trail.

The geometry of the new 2024 Trek Slash in the neutral setting

The new 2024 Trek Slash 9.9 XO AXS on the trail

For this review, we were able to ride the new Trek Slash 9.9 XO AXS 2024 in both size L and XL. We tested the bike over the course of several weeks, putting it through the wringer on the legendary trails of Whistler, Squamish and Della Creek, both on bike park trails and natural trails – and also managed to squeeze in a few laps with freeride legend Andrew Shandro. We also rode the new Slash (in size L) on our home trails around Stuttgart and on some techy Alpine gnar in Switzerland. Testing the new Slash in different frame sizes and countless locations gave us the opportunity to gather plenty of impressions.

Needless to say, an aggressive enduro bike won’t earn you any uphill KOMs, and yet the new 2024 Trek Slash 2024 gets you to the trailhead without too much effort. The rear suspension only bobs slightly and generates plenty of traction on technical climbs, meaning that you can easily make your way to the top of the mountain without reaching for the Vivid’s climb switch. On steeper climbs, the front wheel remains planted on the ground, ensuring excellent steering precision. While on the first test laps the bike was totally quiet, with the idler pulley working discreetly in the background, this changed after a few days, with an increasingly loud rattling noise accompanying us on every climb.

When gravity takes over, the first thing you’ll notice is the high front end and deeply integrated riding position. This inspires huge amounts of confidence, even on the gruellingly steep Canadian trails. The Slash makes you feel at ease from the get-go, encouraging you to keep your fingers off the brakes after just a few corners. If you do brake – which is inevitable from time to time – the rear suspension generates tons of traction without stiffening up excessively if you hit a large bump while decelerating. The wheelbase of the Slash grows noticeably less than with other high pivot bikes, remaining agile and playful even when fully compressed. Overall, the rear suspension provides plenty of support, allowing you to pop off ledges and kickers while at the same time offering enough reserves to cope with botched landings.

The new Slash has direct handling and reacts to steering input quickly and precisely. During this test, we swapped the original wheels and handlebars for alloy models, which helped mitigate the very direct ride feeling, ensuring more forgiving handling in slippery conditions. Even in open corners, the Trek sticks to the chosen line with great composure and doesn’t require you to actively weight the front wheel – and that’s despite the high front end! As a result, you’re always in a central riding position, which conveys huge amounts of confidence in all situations. Overall, the Trek makes you feel as if you had more travel on tap and at the same time is just as agile and playful as bikes with less travel. Trek also seem to have successfully addressed the typical drawbacks of high pivot bikes, like the sluggish handling and unbalanced suspension performance, which can result from the growing wheelbase.

Who should take a closer look at the new 2024 Trek Slash?

The new Trek Slash is aimed at trail rippers, enduro racers, park rats and anyone who likes to get rowdy on gnarly trails. Provided you perform a few basic upgrades, like more robust tires and a tuneable cockpit, the new Slash offers a pretty sweet overall package – we’re pretty chuffed with it ourselves. Even on slower, narrower trails, it’s refreshingly nimble, while the excellent suspension allows you to generate speed by pumping through flow trails, which isn’t always a given with high pivot bikes. In our humble opinion, the Trek Slash 2024 is the next evolutionary stage of high pivot bikes, bringing all the advantages of a high pivot suspension design while at the same time eliminating most of its drawbacks.

Our conclusions about the new 2024 Trek Slash

The new Trek Slash 2024 offers agile, balanced handling and combines it with all the positive traits of a high pivot suspension design, ensuring excellent composure and a plush ride. If you like to open the taps on gnarly enduro trails, we recommend upgrading a few components. This will allow you to boost the Slash’s trail performance enormously with relatively little effort and at a reasonable price. The new Slash slaps a huge smile on your face, whether you’re going for a quick post-work ride on your home trails, racing enduro in the Alps or lapping park tracks – and also makes a great companion for the occasional flowing trail.

• Integrated, confidence inspiring riding position
• Combines excellent composure and agility
• Potent suspension provides plenty of pop and reserves
• Practical features like the integrated storage compartment and mini-tool

• Spec has some blemishes
• Idler pulley grinds lightly when pedalling uphill

For more info, visit Trek’s website.

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Words: Peter Walker Photos: Sterling Lorence, Peter Walker

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About the author.

Peter Walker

As editor-in-chief, Peter is as much a man of action as he is of words. This expert, screw-driver-flexing two wheeled-whizz has many envy-inducing characteristics, including a background in motocross, several EWS race plates to his name, and more than 150 recorded days at Whistler Bike Park. However complex the bike and however steep the trail, he’s probably already nailed it, twice. Oh, and he can do it all on skinny tyres too. When it comes to guiding consumers, Peter cut his teeth at Vancouver’s oldest bike shop and now puts pen to paper on the daily translating this know-how into our editorial plan. When not tearing up Stuttgart’s local trails while testing bikes, he loves nothing more than loading up his self-renovated VW T5 and hitting the road. The fact that he’s a trained paramedic gives his colleagues reassurance out on the trails. So far we haven’t had to call him by his alias ‘Sani Peter’, so here’s hoping he keeps it right side up for the rest of his time here!

• Buyers Guide

• Technical Details

Trek Slash 8 Gen 6 Review

• strorage compartment
• one of the best bikes in this price range
• rides excellent in the downhill
• 25 years warranty
• with 16,5 kg unfortunately a bit heavy

Overall Bike Check

The most importanten ratings of the [bike_model] ⬤ in comparison to the competitor bikes of following categorie: (Enduro up to 4500 €) ⬤ .

Value for Money Check

If you are keen on value for money, this is your chart. It shows you at a glance how many bike you get for 4499 €.

Je steiler der Winkel des Sitzrohrs ist, desto effizienter können Sie in die Pedale treten.

• Frame Slash Alu
• Frame Material Aluminium
• Fork FOX Rhythm 36, Float EVOL-Luftfeder, GRIP-Dämpfer, konischer Gabelschaft, 44 mm Versatz, Boost110, 15 mm Kabolt-X-Achse, 170 mm Federweg
• Spring Unit air
• Remote-Lockout yes
• Damper FOX Performance Float X, 2-Positionen-Dämpfung, 230 x 65 mm
• Gearrange 510%
• Drivetrain 1x12
• Gear Lever Shimano XT M8100, 12fach
• Rear Derailleur Shimano XT M8100, langer Käfig
• Crank Shimano Deore M6120, 30 Z., 55 mm Kettenlinie, 165 mm Kurbelarmlänge
• Cassette Shimano XT M8100, 10-51 Z., 12fach
• Chain Shimano SLX M7100, 12fach
• Brake Set Hydraulische 4-Kolben-Scheibenbremse von Shimano, M6100 Bremshebel, M6120 Bremssattel
• Brake Rotors 203/203
• Rims Bontrager Line Comp 30, Tubeless Ready, 6-Loch-Scheibenaufnahme, Boost110, 15 mm-Steckachse
• Front Hub Bontrager Line Comp 30, Tubeless Ready, Rapid Drive 108, 6-Loch-Scheibenaufnahme, Boost148, 12 mm Steckachse
• Tires Front Bontrager XR5 Team Issue, Tubeless Ready, Inner Strength Karkasse, Aramidwulstkern, 60 TPI, 27.5 x 2.50
• Tires Rear Bontrager SE6 Team Issue, Tubeless Ready, Core Strength-Flankenschutz, Aramidwulstkern, 120 TPI, 29 x 2.50
• Saddle Bontrager Arvada, Streben aus CrMo-Rohr, 138 mm Breite
• Seat Post Größe: S Bontrager Line Dropper, 100 mm Hub, MaxFlow, interne Zugführung, 34,9 mm, 310 mm Länge Größe: M, M/L, L, XL Bontrager Line Dropper, 170 mm Hub, MaxFlow, interne Zugführung, 34,9 mm, 450 mm Länge
• Stem Bontrager Elite, 35 mm, 0 Grad, 35 mm Länge
• Handle Bar Bontrager Line, Aluminium, 35 mm, 27,5 mm Rise, 820 mm Breite
• Handle Bar Width 820

best alternatives

• excellent rear end
• BSA bottom bracket
• UDH derailleur hanger
• integrated cable routing

• robust bike
• definately shredable in the downhill
• quality frame
• higher quality gears than the other bikes in this price range

• storage compartment in down tube
• Maestro rear triangle
• flip chip for geo adjustment
• well protected down tube
• benchmark bike in this price range

• in this price range, it posesses a higher quality chassis than the competition

• space for two bottle cages
• almost invisible cables
• geometry adjustment via flip chip

• Modern geometry
• strong in the uphills
• 5 years warranty

• very good wheels

• independent geo concept
• good complete bike for the price
• with 17,2 kg unfortunately a bit heavy

• Extremely good rear suspension
• coherent overall package
• climbing ace
• superb frame

• better shifting than the direct competition

Expirience with the Trek Slash 8 Gen 6

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First Ride: the Trek Slash+ Sets a High Bar

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• Slash 8 Gen 5