trek slash 9.9 2019 review

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Trek Slash 9.9

• AUS $ NZD $ USD $ CAD $ GBP £ EUR €

Weight / M - 13.70 kg / 30.2 lbs (with tubes)

At a glance

Slash 9.9 is the fastest enduro mountain bike in the lineup, so it’s no surprise it’s the go-to ride for the pros of Trek Factory Racing Enduro. Carbon where it counts, FOX Factory fork, Trek’s exclusive RE:aktiv with Thru Shaft shock, fast-rolling carbon 29er wheels, and a SRAM X01 Eagle drivetrain make this top-of-the-line ride the undisputed king of enduro.

Where To Buy

"This bike rips"

"This bike ripped–like charged-over-everything-as-fast-as-you-want-without-picking-a-line kind of ripped. Yes, it's a lot of bike, but it's hard to find flaws in a bike that can do so much, so well. "

"The new standard"

"Slash is great everywhere and descends with almost the same confidence as a downhill rig. It's nearly perfect and might just be the new standard by which all others are measured. "

"An unflinching machine"

"Slash's blistering speed and downhill wizardry propelled it to the front of the pack. Slash epitomizes just how capable long-travel 29ers have become."

Specifications

• Frame OCLV Mountain Carbon main frame & 1x-specific stays, ABP, Boost148, Knock Block, EVO link, tapered head tube, Mino Link, Control Freak internal routing, Carbon Armor, ISCG 05, G2 Geometry, 150mm travel
• Fork Fox Factory 36 Float, GRIP2 damper, tapered steerer, Boost110, G2 Geometry w/51mm offset, 160mm travel
• Shock RockShox Deluxe RT3, RE:aktiv with Thru Shaft 3-position damper, tuned by Trek Suspension Lab, 230x57.5mm
• Wheel Size 29"
• Tires Bontrager SE4 Team Issue, Tubeless Ready, Core Strength sidewalls, aramid bead, 29x2.40˝
• Chain SRAM GX Eagle
• Crank SRAM X01 Eagle DUB, 32T Direct Mount
• Shifters SRAM X01 Eagle, 12 speed
• Brakeset Shimano Deore XT M8020 4-piston hydraulic disc
• Handlebar Bontrager Line Pro, OCLV Carbon, 35mm, 27.5mm rise, 780mm width
• Saddle Bontrager Arvada, austenite rails
• Seatpost Bontrager Line, internal routing, 31.6mm, 15.5: 100mm, 17.5 & 18.5: 125mm, 19.5 & 21.5: 150mm
• Stem Bontrager Line Pro, Knock Block, 35mm clamp, 0 degree
• Grips Bontrager XR Trail Elite, alloy lock-on
• Headset Knock Block Integrated, sealed cartridge bearing, 1-1/8˝ top, 1.5˝ bottom

Q: Where to buy a 2019 Trek Slash 9.9?

The 2019 Trek Slash 9.9 may be purchased directly from Trek .

Q: How much does a 2019 Trek Slash 9.9 weigh?

A 2019 Trek Slash 9.9 weights M - 13.70 kg / 30.2 lbs (with tubes).

Q: What size wheels does the 2019 Trek Slash 9.9 have?

The 2019 Trek Slash 9.9 has 29" wheels.

Q: What size 2019 Trek Slash 9.9 should I get?

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Trek Slash 9.9 X01: first ride review

• Alan Muldoon
• September 3, 2020

New Trek Slash is manageable and maneuverable, without forcing you to tip-toe down the toughest trails

Product Overview

Trek slash 9.9 x01.

• Fast and easy to ride. Revised geometry and sizing bring it bang up-to-date. Suspension set-up is straightforward and the drain port in the bottom of the down tube should stop the water pooling below the shock.
• All of the cables need shortening to stop them rattling. Trek’s MinoLink is a non-feature as we never clipped a pedal even in the low setting.

Manufacturer:

Price as reviewed:.

First ride review of 2021 Trek Slash 9.9. Trek’s 29in enduro trail blazer returns with more travel and a progressive makeover.

>>> Best enduro mountain bikes: 150 to 170mm travel full suspension bikes

Trek Slash 9.9 need to know

• Trek ups the travel on the Slash 29 by 10mm – it 
now gets a 170mm-travel suspension fork with 160mm out back
• The sizing and geometry both move forward, making the frame longer and slacker than before
• Storage has been added to the down tube, and it isn’t exclusive to the carbon models
• Carbon frame with magnesium rocker link and a 34.9mm seat tube diameter for increased dropper post insertion
• New Knock Block design increases the steering angle from 58º to 72º
• Trek offers a five-model range, starting at £2,650 for the alloy Slash 7

The new Slash offers a razor-sharp ride and point and shoot thrills

Back in 2016, when Trek first launched the Slash 29, you could count the number of long-travel big wheelers on 
one hand. Fast forward to today, and the race to be first at any EWS is consistently contested by the likes of Sam Hill and Richie Rude, both riding 29ers. So 29in wheels dominate racing at the highest level, but what has Trek done to guarantee that the latest Slash 29 is every bit as cutting edge as the original? What it hasn’t done is burn the house to the ground and start over. At first glance, the new bike looks a lot like the old one, but even after one ride, it’s clear that it’s a very different proposition. Yes, the OCLV Mountain carbon frame casts a similar shadow, but everything about this bike is different, from the sizing to the travel; even the Knock Block headset has been updated.

ABP suspension design with tweaked kinematics uses custom Thrushaft shock

Let’s start with travel. The old Slash 29 was a 150mm bike with a 160mm fork. The new version gets 10mm more travel at both ends. I measured vertical rear-wheel travel at 157mm so it can definitely be classed as a 160mm bike. The geometry is not quite as accurate though, as I measured the head angle on the new Slash at 63° in the low setting. That’s one-degree slacker than claimed. Not that I’m complaining, because the steering response feels neutral, and at no point did the bike feel too slack. In fact, I was taken aback when I measured the geometry for the first time and discovered that it was much slacker than it felt. The reach on the size large measured a generous, but not overly long, 475mm, but to get a better picture of the sizing we need to take a closer look at the wheelbase. With 1,273mm spanning the contact patches, the new Slash delivers a footprint that’s every bit as big and as stable as the S4 Specialized Enduro.

Down tube storage compartment specced throughout the range

Trek’s signature ABP suspension has also been tweaked. The progression rate and anti-squat have both increased and the Slash now gets a custom Thrushaft RockShox SuperDeluxe shock, with a choice of three compression settings in the open position and an easy-to-reach lockout. The idea being that you can tune the amount of low-speed support you need to match the terrain. In reality, the difference between the three settings is subtle, so I think most riders will leave it in the middle position and be done with it. In playing with the compression settings I did discover that the bypass for the lockout is really effective though, and you can still ride hard even if, like me, you sometimes forget to open up the shock for the descents .

Knock Block steering range has increased to 72°

One pet peeve with the old Slash was the slack 64.6° seat tube angle. Climb anything remotely steep and your weight ended up too rearward, loading the suspension and resulting in increased pedal strikes. To address this, Trek has steepened up the actual seat angle by one degree (actual measured geometry from both bikes). It doesn’t sound like a big change, but it is enough to give an effective seat angle of 75.5°, more than steep enough to winch up anything that I wouldn’t consider getting off to push up. Trek has also boosted the climbing prowess of the Slash by reworking the chainstay to accommodate a smaller 28t chainring. The bike ships stock with a 30t ring, and if you’re looking for more top-end speed, the biggest chainring the frame will accommodate is a 34t. With the expanded 10-52t range of the latest Eagle cassette however, I can’t see many riders needing a 28t ring on the Slash 9.9 X01. Still, it’s good to have it in your back pocket for big days in big mountains if the chairlift isn’t running.

10-52t Eagle cassette offers wide spread of gears

Other tweaks to the latest Slash see Trek dispense with the Straight Shot down tube and increase the range of the Knock Block steering lock from 58° to 72°, so you can now turn on a dime. The updated frame layout also gives you the option to remove the Knock Block entirely, but if you’re racing I still think it’s a worthwhile safety mechanism, as it should stop cables getting ripped out in a crash.

160mm-travel RockShox SuperDeluxe shock with three compression settings

One of my favourite updates to the Trek Slash 9.9 is the addition of down tube storage, first introduced on the Trek Fuel EX . Best of all, it’s also on the aluminium models further down the Slash range. In an interesting move, Trek has shunned the tube-within-tube design for its internal cable routing, the door in the down tube making it pretty easy to run the cables though the frame and out to the stays. I’m not sure it’s a good move though, as there’s quite a bit of cable rattle. Stuffing an inner tube and some snacks into the down tube quietened it down a bit, but all of the cables on our test bike were really long, and constantly rattled against each other. Fingers crossed, shortening the cables will be enough to improve the acoustics on this otherwise silent ride.

How it rides

I’m always suspicious of any enduro bike that pedals as well as the new Trek Slash 9.9. Sure, they tend to feel amazing when pootling along on your local trails, then you take it somewhere fast, rough and demanding, only to discover the shortcomings in the suspension within the first few turns. Thankfully, the new Trek Slash isn’t one such bike.

Yes, you can still be as precise as a fine-tipped pen when you need to be on a specific line, but the Trek Slash 9.9 also allows you to paint in broad brush strokes, so you can ride with reckless abandon and let your creative juices flow on any canvas. It’s what makes the Slash such an easy bike to ride, and to ride fast. It also makes it very versatile. While bikes like the Specialized Enduro Elite feel a lot like downhill rigs, the Slash is more manageable and maneuverable, without forcing you to tip-toe down the toughest trails. Both bikes share similar geometry, but Trek’s shorter reach actually gives you more wiggle room, not less. And if that sounds counterintuitive, it is. I think it’s because really long front ends tend to pull you into a more fixed riding position, but with the 475mm reach on the size large Slash you can move your weight around more freely simply by bending or extending your arms. This also makes it easier to load the front tyre on flatter trails. Yes, it’s about choosing your battles, so what the Trek loses in raw, straight-line speed it more than makes up for in agility, while still managing to advance the new Slash 29 on all other fronts.

Could the BB height on the Slash 29 be a hair lower? Sure it could, as I never so much as kissed a pedal on the ground, even with 175mm crankarms and the MinoLink in the low geometry setting. Did it slow the Slash 29 down any? Not one jot.

Trek Slash 9.9 X01 Enduro MTB review

We took the trek slash 9.9 x01 to our toughest local trails to see how its new shape and unique shock translate to the real world.

BikePerfect Verdict

Ragingly fast and precise enduro race bike with all-day efficiency and a ton of practical details for those who can afford and appreciate it

Phenomenal rear suspension

Awesome aggro geometry

Precision accuracy

High control cockpit

Internal storage

Efficient pedaling

Threaded BB

Optional steering lock

More confident with switched tires

ZEB fork requires some patience

Deserves better wheels

Short dropper on small sizes

Seriously grounded rather than playful

Why trust BikePerfect Our cycling experts have decades of testing experience. We'll always share our unbiased opinions on bikes and gear. Find out more about how we test.

The Trek Slash 9.9 X01 is the brand's flat-out fast long-travel 29er set to do battle against the best enduro mountain bikes . The 2021 model gets a new frame, new geometry, new features and RockShox's take on Trek's proprietary Thru Shaft shock technology. The result is a seriously accurate, phenomenally controlled, track or trail dominating high-velocity weapon that’s still pedal efficient and loaded with practical details for big days out. You’ll need to be regularly hitting big stuff at full gas to get the most from it though, and we’d switch the tires round, too.

Design and geometry

The Trek Slash 9.9 X01's layout is the same as it's always been. Massive shallow S-shaped downtube, stout and oversized ‘brow’ 8 headtube, steep top tube and a thick square section seat tube with forwarding kink to mount the short rocker link that drives the shock down towards the BB. The linkage attaches to the long braced seat stays via Trek’s much-copied ‘Mino’ link that can be flipped to change angles by 0.5 degrees and BB height by 7mm. The stays meet at an ABP (Active Braking Pivot) concentric with the rear axle and then the deep chainstays kick back up to the main pivot just higher than the top and fractionally behind the center of the 30T chainring.

For this year though, that chainset mounts via a threaded rather than press-fit bottom bracket. The massive downtube now has a hatch under the full-size bottle cage to access internal storage (pouch included). The seat tube is 34.9mm in diameter for the stiffest possible dropper shaft and there’s an extra replaceable guard under the downtube to protect the OCLV Carbon if you’re shuttling over the tailgate of a pickup. The internal control routing is muffled with internal clips and bolted entry inserts. The neck of the downtube is no longer dead straight either, so there’s enough clearance for a fork to spin right around. That means the ‘Knock Block’ limiter key in the top tube works with headset spacers that have 72-degrees of rotation on either side of straight (rather than the previous 58-degrees) or you can just remove the key entirely for a free spin.

The other angles of the bike have been altered too, bringing it back in line with the c urrent crop of enduro bikes. Depending on where you have the Mino Link chipset the head angle is now 64.1-degrees or 64.6-degrees and the effective seat angle is 75.6-degrees or 76.1-degrees. Reach has been extended significantly on all sizes with the large size now stretching to 486 or 491mm with a 450mm seat tube. Travel also goes up by 10mm to 160mm at the rear with a 170mm fork. These features and geometry changes also appear on the alloy framed bikes, including the storage which, according to Trek’s designers, was one of the hardest parts of the whole frame development process. Working around the packaging demands of the unique shock was another headache, but the end result is you can fit any damper you want into the Slash frame and the kinematic works with coil too.

• Best enduro mountain bike
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Components and build

The 9.9 is the top Slash available in the UK and comes with the choice of two of the best MTB groupsets , a Shimano XTR spec or the SRAM X01 version we tested. As you’d hope that gets you an almost complete set of X01 gearing (the chain is GX) complete with carbon armed chainset, 30T ring and an MRP chain guard/guide as standard. Brakes are powerful and widely adjustable SRAM Code RSC with a 200mm rotor up front, but a mid-sized 180mm rear. The tires reverse that control balance with a 29 x 2.4in lower tread SE4 tire on the front and a blockier 29 x 2.6in SE5 on the rear, both featuring reinforced Core Strength carcasses. You get Bontrager’s affordable Line Elite 30 carbon rim wheels as standard which aren’t as light as the best mountain bike wheels (just under 1,900g a pair) but the OCLV lay up is seriously tough. They come set up tubeless as standard too so you don’t have to fight with the tight fit. Bontrager supply the keyed stem for the Knock Block steering lock, the extra-wide 820mm carbon bar and the short-as-possible 35mm stem. The oversized 34.9mm shaft dropper post ranges from 100 to 200mm stroke depending on frame size. All 9.9 bikes get 170mm of travel from the huge 38mm stanchion RockShox ZEB fork, with 160mm of rear suspension controlled by a custom Super Deluxe Push shock. There are two lower-priced carbon models - 9.8 and 9.7 - which get a Thru Shaft shock, as well as two alloy models with conventional shocks starting with the Slash 7 at $3,499.99/£2,950. 

Ride, handling, and performance 

The Slash has always been one of the stiffest-feeling enduro bikes around. While the downtube has now been lifted and curved at the head end and cut open for the storage hatch, the OCLV Mountain Carbon chassis still has an immediate rock-solid feel. While it doesn’t get the lifetime ‘no questions asked’ warranty of similarly stiff but heavier frames like the Santa Cruz Megatower and Yeti SB-150, you do get reduced price replacement under Trek’s Carbon Care program.

The big 820mm bars add extra power steering leverage and the 38mm stanchions on the ZEB fork are unerringly rigid under braking or turning. That does count against them at first, as it takes a while for the seals to ease up and smooth out. While the smaller volume tire means it cuts rather than drifts in slop, the shallower tread and correspondingly lower grip of the 2.4in SE4 front tire was a limiting factor of just how hard we could push the Slash at first. However the fix is easy: we switched the chunkier, hard railing SE5 rear tire onto the front and put the SE4 on the back. This improved our confidence noticeably, particularly for UK winter conditions.

• Best mountain bike wheels
• Best mountain bike tires

To put tire performance into perspective we are also talking about an enduro bike that already sneers at normally challenging terrain with such arrogant contempt it requires a significant reset of your expectations. While it will roll efficiently over tamer terrain and lamer line choices, it’s when you give it the space and speed to really open up that the Slash shifts from sorted to superlative.

The slacker, longer, lower geometry, with deliberately slightly lengthened chainstays, is locked in with outstanding axle-to-axle stiffness laying down a super stable stance. It’s the Thru Shaft shock that really capitalizes on the trail-crushing potential of the chassis, though. By pushing the shaft right through the body it avoids the sprung resistance and stiction of a conventional oil volume compensating internal floating piston, so it feels more reactive, accurate and - for want of a better word - relaxed when you’re at the ragged edge. The combination of carefully curated shock rate and the naturally neutral wheel behavior of the ABP pivot means it never feels lost, slow or wallowing despite the 160mm stroke. The progression from supple, traction-hungry, chatter-erasing initial stroke (helped by the bigger 2.6in rear tire) to shoe-sole flexing, berm-blowing mid-stroke support and slap, and spike-free handling of the biggest drops, is utterly consistent and precisely communicative too. While the default center position of the low-speed compression adjustment is a great balance for all-round riding a simple pull and click to more or less damping makes an immediate and appreciative difference. Perfect for dialing in exactly the shock feel you want for each section of the trail without having to disturb the baseline settings. Initial setup is also easy thanks to Trek’s online setup calculator and the use of a numbered rebound adjuster rather than a manual count dial.

The only downside to the impressive back end, is that the multi-adjustable and normally awesome feeling ZEB Ultimate fork regularly felt shaded by the chassis control when the Slash was getting into its stride. Wonderfully feedback-rich brakes, high strength carbon rims (that survived plenty of rim hits when we got a temporary slow flat, sturdy tires (which stayed on when we had that flat), plenty of seat post drop (on the L and XL at least) and the extra peace of mind from the frame armor, chainring protector and chain retainer mean no worries about the rest of the spec either.

While attacking the most aggressive lines and straight-lining the most brutal terrain at race velocities is where the Trek is designed to fully flex its performance, it won’t sulk too badly if you’re not an Enduro World Series-caliber pilot on an appropriately terrifying track. What the Bontrager SE4 tire lacks in glory grip, it gains in easy and efficient rolling and when we switched the rubber round the Slash can properly hustle. The super fast pick up of the rear hub and the permanently poised suspension help offset the chunky weight of the Line Elite wheels too. Add the efficiency amplifying stiffness of the frame and our testers were consistently surprised how well the Slash pedaled even on prolonged climbs or road/fire road transition sections and we rarely used the ‘locked’ position on the shock. Excellent rear wheel traction and communication means you’ll rarely dab a foot on the way back up even the most technical trails either, although we did nudge the saddle forward on the rails to balance the throwback of the post in the steeply sloped upper seat tube. Inevitably the big wheels, super stable handling and 14.6kg weight mean it can become a wrestling match compared to a lighter, shorter and/or 27.5in wheeled bike if you let speed drop too low or lose focus and swap the racing line for a swamp.

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Most bikes in the Enduro category claim to be race machines but few - if any - communicate their extreme course-crushing performance with as much clarity and authority as Trek’s new Slash. Evolved, stability-boosting geometry, superbly sorted suspension baseline with dialed on-the-fly fine tweaking and excellent pedaling response, make it one of the most speed-hungry, high-velocity bikes we’ve ever ridden. It’s tough and seismically assured enough to hit up the bike park but loaded with the practical details and pedaling efficiency to make it a big day happy, no limits trail bike too. As sturdy as they are, sub £800 ‘budget’ carbon wheels don’t sit right on an over 8K bike, it definitely deserves a grippier front tire and even the mighty ZEB fork can feel shaded by the unique Thru Shaft back end and carbon chassis. 

Test conditions

• Temperature: 0-7 degrees, rain, sleet, ice, occasional weak, watery sun
• Surface: Wet, muddy, rooty, rocky, natural and bike park
• Routes: Natural wild trails, old school DH and red and black, rocky bike park 

Tech Specs: Trek Slash 9.9 X01

• Price: $8,499.99 / £8,250.00
• Head angle: 64 degrees
• Frame material: OCLV Mountain Carbon
• Sizes: S-XL (L tested)
• Weight: 14.6kg
• Wheel size: 29-inch
• Suspension: RockShox ZEB Ultimate 170 mm travel, RockShox Super Deluxe Ultimate 160 mm travel
• Components: SRAM X01 Eagle 10-50T 12-speed gearing, shifter and 30T chainset, GX Eagle chain. MRP Chain guide and guard SRAM Code RSC brakes with 200mm front and 180mm rear rotors. Bontrager SE4 Team Issue 29 x 2.4in front and Bontrager SE5 Team Issue 29 x 2.6in rear tires on Bontrager Line Elite 30, OCLV Mountain Carbon wheels. Bontrager Line Pro, OCLV Carbon 820mm carbon bar and Bontrager Line Pro, Knock Block 35mm stem, Bontrager Line Elite Dropper 170 mm travel dropper post, Bontrager Arvada Austenite railed saddle.

Guy has been working on Bike Perfect since we launched in 2019. Hatched in Yorkshire he's been hardened by riding round it in all weathers since he was a kid. He spent a few years working in bike shops and warehouses before starting writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.

Current rides: Cervelo ZFS-5, Forbidden Druid V2, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg

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Trek Slash 9.9 29 Race Shop Limited review

Race-tuned big-wheeler proves red bikes really are fastest

Josh Patterson / Immediate Media

Josh Patterson

Superbly shaped, jaw-droppingly stiff full-carbon frameset; ultra-sensitive, maximum grip but HD communicative and immaculately poised Fox suspension; mostly excellent wheel, tyre and component pack

TALAS fork adds cost and drag; 125mm Bontrager dropper is short and slow

Trek’s Remedy 29er was one of the most dominant bikes on the Enduro World Series. It lead the way for other companies to develop similar race-ready 29er enduro rigs. So it was quite a surprise when Trek discontinued its winning model. The outstanding performance of the Slash clearly owes a lot to lessons learnt with the previous bike, though.

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Made from Trek’s ‘OCLV Mountain Carbon’, the Slash frame is fairly light but also massively stiff, letting you chop into the most aggressive lines with the force of a butcher’s cleaver. Cartridge bearings are used at the shock mounts to make the damper feel as sensitive as possible.

The Boost 148mm rear axle that Trek pioneered slots straight through the centre of the rear ‘ABP’ pivots, while deep, symmetrical, single-ring-specific chainstays complete the rear end.

Impact bumpers protect the belly and chainstay, and there’s another under the down tube throat in case the ‘Knock Block’ — Trek’s unique steering lock limiter, which is integrated into the top tube — slips and lets the fork whip round.

Trek pairs the top-end Fox Float X2 shock with a matching 36 TALAS fork, which can be dropped from 160mm to 130mm for improved climbing. On the trail, our Superbike of the Year testers rarely used the external travel adjustment but relished the fact it’s the high and low-speed tunable ‘racer’s favourite’ RC2 model, not the climb-lever-equipped FIT4 version.

The TALAS feature does add a noticeable amount of seal drag, which hampers the fork's small-bump sensitivity. It also adds cost to an already pricey bike. A standard 36 RC2 would be our choice.

SRAM’s X01 Eagle group with monster 50t sprocket makes climbing easier, and the 10t cranker cog means even this missile won’t be short of DH drive.

In-house Bontrager kit is used elsewhere and it has high and low points. The DT Swiss-based hubs of the Line Elite 30 wheels have upgraded pickup to create a fast and tight wheelset, and the SE4 tyres are all-conditions favourites, with a great tactile feel.

While it’s a slightly odd shape, the 780mm carbon bar is a good width once you’ve got the rotation right and the 35mm stem is spot on. The Drop Line seatpost does have it's downsides — we’d prefer a longer-than-125mm stroke and faster action.

Detail niggles aside, the ride of the Slash is jaw-dropping, even in such an exotic line-up. For a start, the sensitivity of the bearing-mounted shock and ABP architecture is phenomenal, so traction is exceptional whether you’re flat out with heels dropped, wrenching in a couple of pedal revs between turns or winching up a techy climb.

That sensitivity extends right through the stroke too, so no matter how you tune the Float X2 shock, it responds with impeccable accuracy. Add the 29in wheels and the Slash is genuinely DH bike fast in how it carries speed through roots, rocks, wheel-eating holes and stepdowns.

Not only is the suspension on point but the whole bike feels quiet, utterly poised and HD feedback-rich, no matter how much work the wheels and dampers are doing underneath. It’s as close as you’ll get to putting your head on a gimbal, letting you spot lines and stay on the attack when the trail would normally be an intimidating blur.

The hyper-stiff frame and fork let you make maximum use of the relatively slack 65.5-degree head angle, sorted cockpit dimensions and stability-boosting 460mm reach (large size).

While the Slash sits quite high on paper, the easy shock compression means it feels scythe-sweepingly low on the trail. It doesn’t just hit every mark, it opens up psychotically aggressive lines you’d never even look at normally and hits them flat out with stability, grip and confidence to spare.

While the shock looks overactive under pedalling, the Trek is actually a remarkably efficient and swift climber over the most staccato surfaces if you just get on with the job, and more stable suspension is only a flick of the climb switch away. Considering it descends like a freight train, the Slash is surprisingly light and fast-rolling when it comes to tapping out the miles too, making it a truly stunning all-rounder from first sight to last light.

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2020 Trek Slash 9.9

A 29″ carbon frame full suspension enduro bike with ultra high-end components. Compare the full range

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Based on frame geometry and build specs.

A bike with lower gearing will be easier to ride up steep hills, while a higher top end means it will pedal faster down hills.

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Mar 2021 · Lydia Tanner

The Trek Slash has been 29-inch-only since 2016, and the 2021 version is evidence of its head start in the big-wheel enduro category.

Superb high-speed stability

Great traction in variable terrain

Supple and generous-feeling suspension

Less maneuverable at slow speeds

A lot of bike to get back up the hill

Read Review

Riding a bike like the Slash over the winter on the North Shore is a rough test scenario, but Trek's newest long travel trail bike has proven up to the task...

Feb 2021 · Guy Kesteven

We took the Trek Slash 9.9 X01 to our toughest local trails to see how its new shape and unique shock translate to the real world

Phenomenal rear suspension

Awesome aggro geometry

Precision accuracy

High control cockpit

Internal storage

Efficient pedaling

Threaded BB

Optional steering lock

More confident with switched tires

ZEB fork requires some patience

Deserves better wheels

Short dropper on small sizes

Seriously grounded rather than playful

Dec 2020 · Mike Wirth

The new Trek Slash 9.9 X01 sees many updates making it an even more capable all-mountain, enduro mountain bike. See how it performed.

Dec 2020 · Mike Kazimer

The Slash received multiple updates for 2021, but it's still an enduro race machine at heart.

Light and stiff frame – encourages you to go fast

Great shock tune

In-frame storage

Wide range of available frame size options

Seat tube angle could still be a bit steeper

Shorter cranks and an even longer dropper post would have been nice to see

Oct 2020 · Spencer Johnson

The venerable Trek Slash is back for 2021, armed with more suspension travel than ever before. The new Trek Slash 9.9 X01 comes equipped with the ever-capable, 170-millimeter RockShox ZEB Ultimate fork and a custom, 160-millimeter RockShox Super Deluxe Ultimate shock, placing it squarely in the hard-charging enduro category. For me, one of the most welcome updates for the new Slash is the seat angle, which has been steepened to 75.6 degrees, putting the rider’s weight directly between the wheels—and making for a much more comfortable seated position while climbing. The relatively long reach of 486 millimeters, together with the mid-length chainstay of 437 millimeters, creates a bike that stays firmly planted while you sweat your way to the top of a mountain. But the most impressive feature of the new Slash is its impressively light weight—something I wouldn’t automatically expect from a bike in the longer-travel range, especially one with 29-inch wheels. The lightweight frame construction and ultra-light build of the 9.9 X01 version I tested was noticeable from the moment I started huffing up my first climb.

Trek was an outlier with the previous Slash when they went all-in on enduro 29. Things have changed, but the Slash stays true to its mission: Slashing.

Trek redesigns the Slash for 2021, going longer, lower and slacker to make a mean enduro machine with a few tricks up its sleeve.

Last updated December 20 Not listed for 1,231 days

The New Trek Slash 9.9 Plows As Expected, But Pedals and Pops Too!

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I’m lucky to live in an area with delightfully steep and rough terrain. Because of that, long-travel bikes like Trek’s Slash are right up my alley. The 2024 Slash’s generation 6 frame is ready to get rowdy with a new high-pivot suspension linkage and 170mm travel. The bike simply plows through rough terrain, but remains impressively capable of getting itself back uphill for more laps.

The short story is I have nothing negative to say about Trek’s transition to the high-pivot suspension linkage. The new Slash is buttery smooth, yet offers a surprisingly poppy ride and still climbs as aggressively as their ABP bikes. The Slash is not the lightest bike, but that’s kinda fair since it’s such a beast.

2024 Trek Slash: Key Specs

For full details on the new Slash lineup, check out my launch article from September.  Before we get into the ride review, here are a few key specs and features of the 2024 Slash.

Most models of the Slash, including the 9.9 X0 AXS T-Type model I tested, come with full carbon frames. There are two aluminum complete models and an alloy frameset in the lineup. Of course, the biggest update for the Slash is the high-pivot linkage. The Slash now offers 170mm rear travel and all models come with 170mm forks.

Another interesting change for the new Slash is that they all come stock with a mixed-wheel setup (except small frames, which run dual 27.5” wheels). Frame sizes medium and up can run a 29” rear wheel, but you must buy the geo-correcting shock mounts from Trek. You’ll also have to remove the rear fender, as it doesn’t leave enough clearance for the 29” rear wheel.

The Slash boasts very slack and adjustable head tube angles, which can be altered by adding Trek’s angle adjust headset cups. Trek also incorporated their leverage rate chip into the shock mounts, offering ‘less’ and ‘more’ progressive settings. The Slash does not have Trek’s mino link anymore, as the other adjustments offer plenty of opportunity for fine tuning. Trek also decided to do away with their Knock Block headset.

A nice finishing touch for the carbon-framed Slash is Trek’s new ‘Carbon Armor’ frame protection. Before they’re painted, Trek wraps the frames with an impact-resistant film.

The Slash 9.9 X0 AXS T-Type (size M/L) weighs 35.76 lbs with pedals. Considering this is a beastly 170mm travel bike, and has extra hardware for its high pivot linkage, I guess I couldn’t hope for much better. I have to say though, with a full carbon frame, carbon rims and a lightweight carbon bar/stem combo, I was a bit surprised to see this high-end model come in over 35lbs.

Geometry/Fit:

At 5’10” and riding a M/L frame, I’m very happy with the Slash’s geometry. For this article, I’ll discuss the geo of my test bike, which has neutral headset cups and its stock mixed-wheel setup. Unfortunately, I didn’t have a compatible 29” rear wheel on hand to test.

So you know, the geometry remains very similar if you install a 29” rear wheel. Aside from the chainstay length growing by 6mm, there are very minor differences in certain angles and measurements. Check out Trek’s website to see all the different geo charts.

My test bike’s head tube angle is 63.3°, and I loved it. The slack steering angle tackles steep and rough terrain like a champ, but as I’ve found with slacker long-travel bikes it doesn’t hamper climbing ability by much. I’m not sure if I would go any slacker for trail riding, but if I set up a Slash for bike park shredding I’d be tempted to try the slacker headset cups. At 63.3° the Slash offers a ton of stability and feels great on steep downhills, yet the bike still doesn’t feel overly long or clumsy on tight switchbacks.

Helping get you uphill is a steep effective seat mast angle of 77.3°. With a lengthy reach of 468.1mm, that steep seat tube leans you into a well-balanced position over the bike. This is one of the longer bikes I’ve ridden, but I never felt like my arms were overextended.

With Trek’s size-specific chainstays, the M/L mixed-wheel Slash’s rear end measures 434.2mm. This middle-of-the-road length, especially with the 27.5” rear wheel, keeps the Slash pleasantly agile. Overall the bike feels long and very stable at speed, but the rear end simply whips around corners. I should note this is the first MX bike I’ve ridden, and I quickly understood why people like them. I’ve never been amazing at cornering, but I felt like I suddenly got better when I hopped on this bike!

Looking at the numbers, the Slash isn’t the lowest bike out there. The standover height is not particularly low at 766mm, and neither is the BB height of 351mm. Up front the stack height is 632.1mm. I don’t remember banging pedals or the 165mm cranks very much, so the BB height allows decent clearance on the trail. It’s higher than some competitors, but the Slash’s long wheelbase and slack steering still provide a very stable ride.

On my first ride with the Slash, I did notice the slightly sluggish roll of the 27.5” rear wheel. I had been riding niners for a few weeks before the Slash arrived, and I have to admit I felt the difference right away.

That said, I quickly forgot about the smaller rear wheel and adapted to the Slash’s ride. While I’ll never say it’s the best climber I’ve ridden, it does very well for how burly a bike it is. Shedding some weight and running 29” wheels would make it climb better, but that’s not what the Slash is all about. Trek describes this bike as ‘70% downhill, 30% uphill’ but I’d say it climbs a little better than that suggests. 

I’ve always found Trek’s ABP linkage to climb aggressively and powerfully, and the new high-pivot version doesn’t behave too differently. Trek tuned the new Slash’s anti-squat to be pretty close to their Top Fuel XC/trail bike, so your pedalling inputs won’t force you deep into the Slash’s lengthy travel.

Climbing singletrack with the shock in firm, I’d get about 50% travel. In open mode, the shock would dip a bit further but top out around 60-65%. I’ll take the slightly rougher ride and increased pedal support from the shock’s firm mode, because in either setting I had solid traction on any singletrack climb. In firm mode the Slash doesn’t erase small bumps; you still feel the trail below you with the shock resisting those low-speed impacts.

In open mode, the shock helps soften those small bumps and offers a more comfortable ride. Fortunately, there is little sacrifice in pedalling efficiency when the shock is left open, so riders looking for maximum traction can opt to climb this long-travel machine wide open with practically no penalty.  

With the rear shock left wide open, I tried some hard pedaling and sprinting on paved roads to see what the Slash’s high-pivot linkage would do. Sitting down and mashing the pedals as best I could, I could not get the bike beyond 40% travel (from 30% sag). Even standing up and sprinting, I only made it a bit further than 40%. It’s clear that Trek’s linkage handles pedaling forces very well. The bike was in its ‘more’ progressive position for this test, but I don’t think it would behave much differently in the ‘less’ setting so early in the travel.

It’s always nice when a bike has no unusual setup requirements. With the Slash, I pumped the shock up to body weight in psi, set rebound/compression to my usual ranges, and the bike was dialed. Right away I was getting full travel from the rear shock (with the leverage chip in ‘less’ position), which is sometimes an issue for my 145lbs self.

Descending:

I’ve always found Trek’s MTBs to be great at gobbling up bumps, but the high-pivot Slash is even better. I noticed it does particularly well at eating up mid-sized bumps, happily plowing through roots and rocks. The rearward axle path does a great job of numbing bigger hits and keeping the Slash feeling planted on rough trails. I found the bike cushions landings very well, especially on little jumps that send you right onto a rocky or rooty patch. 

It’s hard to pinpoint a weak spot in the Slash’s suspension. At higher speeds, the bike smooths out small bump chatter very well, and as noted above it rounds off medium and big hits nicely.

Furthermore, with all that squish when you want it, the Slash actually seems to pop off jumps a bit better than the 2019 Remedy I owned for several years. It also springs out of corners surprisingly well, as I’ve traditionally found Treks to be a better example of plowy than lively and poppy. It seems the big Slash has maintained an impressive degree of mid-stroke support.

Just looking at this frame, you’d probably expect it to be stiff and you’d be correct. Just like the previous generation Slash and Fuel EX I rode, I found the 2024 Slash’s frame offers a solid, commanding feel as you charge down rough trails.

For most of my rides, I had the leverage chip in its ‘less’ setting, but I flipped it to ‘more’ for my last few test laps. Interestingly, the ‘more’ setting doesn’t seem to increase bottom-out resistance by much; I hit full travel on a typical trail loop in the first ride in this setting.

What I found is the rear wheel does feel like it’s resisting bigger, sharper hits more. Under my lightweight self, the Slash felt a bit less plowy and the back wheel would bounce a bit more facing sharp impacts. The only time I got a good ‘thunk’ out of this bike’s rear end was while riding in the ‘more’ position. For me, there’s no question I’d keep the Slash in its ‘less’ setting. The biggest joy of this bike is how capably it sucks up rough terrain, and I’ll take all the squish it has to offer.

The Slash’s 27.5” rear wheel offers good clearance. I rode the steepest trail in my local network and didn’t hit my ass on the tire once (and I have on my personal 29er)! As mentioned above, the mullet setup also has an immediately noticeable benefit in the corners. After you initiate a turn, you then feel the back end hook in and bring you around quicker than a 29er would.

Chain Drop?

Some of you may have seen reports of the new Slash dropping chains. Apparently, some of the bikes were sent out with the lower chain guides incorrectly installed, and some riders had issues with chain drop. After many rides on my test bike, I got the notice from Trek and found out it was indeed not to spec… however I never dropped a chain.

By the time I got the info on how to correct the situation, winter had set in and my testing was pretty much done. I rode the bike two or three more times without even adjusting the chain guide, and still never once lost my chain.

To fix this issue Trek is making sure all Slashes will now be shipped out with the correct setup. They’ve also notified dealers on how to fix the issue, and as an extra precaution, they’re supplying upper idler pulleys with longer teeth to dealers at no charge. As of early 2024, anyone with a new Slash can go to their local shop and have the revised idler installed.

If you’re wondering about potentially increased drag with the high-pivot chain line, I can’t say I noticed anything measurable. Of course, this is a brand new bike; over time the upper pulley might produce extra drag if the bearing wears out, but with all new components the Slash pedalled like any other MTB.

Components:

A RockShox Zeb fork was the obvious choice for the burly new Slash. The 9.9 X0 AXS T-Type bike I rode gets the Ultimate model with a DebonAir spring and Charger 3 RC2 damper. The fork is stiff, offers great initial sensitivity, and sucks up bigger hits in class-leading fashion.

Out back, RockShox’s Vivid Ultimate rear shock performed great with very little fidgeting. The stock tune feels pretty linear which works well for a smaller guy like me, allowing full squish on nearly any descent. The shock’s firm mode resists low-speed impacts nicely, but doesn’t ride like you’re at near-lockout firmness.   

Overall I had great performance from the SRAM X0 Eagle AXS T-Type drivetrain and dropper post. However, the dropper post suddenly stopped working in the middle of my third ride. Once I got home I simply paired up the post and control pod, and since then everything has worked perfectly. 

The 30t chainring and 10-52t cassette provide a vast gear range for trail riding, and shifting performance was basically flawless throughout my test. I unfortunately gave the T-Type X0 derailleur’s cage a good smash and a nasty bend, but didn’t notice right away because gear shifting was still fine! The derailleur will skip lightly when backpedaling but it still doesn’t derail at all, which is impressive.

Bontrager’s Line Pro 30 carbon wheels held up great through my test, showing no signs of damage or warpage. The Slash’s wheels come tubeless with a Bontrager SE6 Team Issue 29×2.5” front tire and a Team Issue SE5 27.5×2.5” rear tire. These tires offer a well-rounded tread that rolls fairly fast and provides good grip on all surfaces. 

Bontrager’s RSL carbon bar/stem combo is hard not to enjoy looking at! The rise is 27.5mm, stem length is 35mm, and the bars come stock at 820mm wide . The 7° backsweep and 6° upsweep is a bit more up and less back than most bars I’ve ridden, but I found them comfortable. I would have liked to ride the full width, but my bars had been cut to 795mm. I rode these bars uncut on the previous generation Slash and was surprised how much I liked them.

SRAM’s Code Silver 4-piston brakes with 200mm rotors had no shortage of power, reeling in this big bike with great modulation and more than ample bite force.

The 170mm dropper post on the M/L frame gets low and out of the way. I didn’t have any problems riding with the Bontrager Arvada saddle, but I find it a bit hard and not the most comfortable. 

The Slash’s rear fender seems to work fairly well. After a wet, snowy ride I still had mud spray all the way up the back of my jacket, but less than what I expected. I also noticed the back of the dropper post and under the saddle weren’t that dirty.

Trek’s Carbon Armor seems to help resist frame damage well. After close inspection, I could only find a few very minor knicks or scratches on the Slash. The down tube, BB shell and all the areas prone to rock strikes from the rear wheel remain basically unscathed. 

Frame Storage:

Trek’s in-frame storage was revised for the Slash, offering a larger door and an updated latch. The storage compartment is easy to open and close, and the included Bontrager BITS tool roll has spots for a CO2 canister, an inflator head, a multi-tool, and a tube (although it’ll have to be a thin one). Trek added ‘chunnels’ inside the Slash’s frame to keep your tool roll/cargo from snagging on your cables. They seemed to work well, I had no issues with anything snagging inside the frame.

Bontrager’s BITS steerer tube multi-tool is also included on all Slash 9.9 models – a nice finishing touch for these top-tier builds! 

The 2024 Trek Slash 9.9 X0 AXS T-Type retails for $9399. Frame color options are Daintree, Lichen Green (as tested), or Argent Drizzle.

trekbikes.com

Steve Fisher is a staff contributor for Bikerumor. Steve has been writing about trail, enduro and downhill mountain biking (plus a few commuter bikes) for seven years. Prior to that, Steve wrote for Whistler Traveller Magazine and Mountain Life Magazine. Steve is based in Pemberton, British Columbia, an area that offers plenty of challenging world-class singletrack and makes for great photos!

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Trek Slash 9.9 29 RSL - Review

Cool Features

2021 Trek Slash 9.9 on test – Is this the new enduro bike benchmark?

The Trek Slash caused quite a stir when it was launched in 2016 and played a key role in shaping the 29er enduro bike category. Now, Trek have finally presented its successor, the 2021 Trek Slash 9.9 – with more travel, updated geometry and a practical storage compartment. Will this be the new benchmark?

The most important updates of the 2021 Trek Slash in a nutshell

The new Trek Slash has big shoes to fill! Hardly any bike was as popular in the scene as the 29er preceding it, but it was getting on in years. Trek have increased the travel of the new Slash by 10 mm to 170 mm up front and 160 mm at the rear. The geometry has also been fundamentally revised: the reach is longer, the seat tube angle is almost 2° steeper and the head angle is slacker (now 64.1°). The bottom bracket was lowered by a further 6 mm, despite having more travel, bringing the BB drop to 29 mm. As with the Fuel EX , the American brand have equipped the Slash with a storage compartment in the down tube of both the carbon and aluminium frames.

Looks like a … Trek! There’s no denying the new Slash’s heritage.

Trek have also improved many details of the Slash, giving the bike a new Thru Shaft Super Deluxe shock specially made by RockShox, a revised Knock Block that doesn’t limit the steering quite as much, a threaded bottom bracket and bigger frame protectors. On top of that, the new Trek Slash comes with a 34.9 mm dropper post offering up to 200 mm of travel.

The changes made to the 2021 Trek Slash at a glance:

• longer and slacker geometry with a steeper seat tube angle
• more travel – 170 mm at the front, 160 mm at the rear
• convenient storage compartment in the down tube (aluminium and carbon frames)
• revised Knock Block offering a wider steering angle (72° instead of 58°)
• Specially developed Super Deluxe shock with Thru Shaft technology
• bigger frame protectors
• 34.9 mm dropper post with up to 200 mm travel

The frame of the 2021 Trek Slash in detail

Like its predecessor, the new Trek Slash is available as an aluminium or carbon version. The kinematics and geometry of both versions are identical. Trek are also the first company to integrate the practical storage compartment in the down tube on an aluminium frame – awesome! Like its predecessor, the rear linkage of the new Slash also pivots on the rear axle. As such, the rear suspension should remain active while braking. Trek also continue to rely on their so-called Mino-Link on the new model, allowing you to adjust the geometry by around 0.5° and the bottom bracket height by 6 mm – but we don’t know of anyone who actually uses it. We only ever rode the old and the new Slash in the slack setting.

The Thru Shaft technology on the shock already proved itself on the predecessor, which creates less internal friction thanks to the continuous shaft and the lack of IFP and its seals. For the new model, Trek worked with RockShox to improve on this technology. Instead of using a specially manufactured body, it is now based on the Super Deluxe which allows you to adjust low-speed compression in three stages and thus tune the bike to suit different trails. Flow trails = more compression; steep natural trails = less compression. Another update is that the rebound clicks are now numbered, making it much easier to play with the setup. If you’d prefer using a different shock on the Slash, you can do so without any problems. Most 230 x 62.5 mm Trunnion mount shocks should fit into the rear triangle (e.g. FOX DHX2, FOX X2, RockShox Super Deluxe Coil, FOX DPX2 and MRP Hazard). According to Trek, the Slash is also compatible with coil shocks. The only shock that won’t fit is the classic Super Deluxe air shock because of the position of the lockout lever. Despite having longer travel, Trek have managed to retain the kinematics of the previous Slash, only increasing the overall progression by 2%.

Trek have reworked the details too, equipping the Slash with a threaded BSA bottom bracket, which is much easier to replace than a press-fit version. The down tube protector has been lengthened, but it can also be split in two to save weight, though we wouldn’t know who would want to do that. The cables are routed internally and are secured in place at two positions in the storage compartment, negating the need for foam sleeves or dedicated cable channels inside the frame. Trek have also designed the new Slash to accommodate longer dropper posts, speccing a 200 mm travel Bontrager model on the XL bike. Size L comes with a 170 mm version, while sizes ML and M are fitted with 150 mm travel posts. The smallest size S gets a 125 mm model. The travel of the dropper post can be reduced with spacers if need be.

For the rear end, Trek continue to rely on the established 148 mm Boost standard that they introduced. To increase the clearance around the chainring, they choose to fit the latest SRAM or Shimano cranks with a 55 mm chain line. We wrote a separate article explaining why we think the new Super Boost Plus standard makes little sense, so we’re glad that Trek didn’t go down that route.

An analysis of the Slash’s geometry

You can tell the age of the previous Slash by its short reach and the very slack seat tube angle. Trek have updated both of these aspects on the new model. In size L, the new bike has a reach of 486 mm, 33 mm longer than previously. The chainstays have only increased by 2 mm to 437 mm. The seat tube angle has been made 1.9° steeper, but at 75.6° it’s still pretty slack by today’s standards, especially as the effective angle slackens the further the dropper post is extended. The bottom bracket is lower than its predecessor too, but the 29 mm drop isn’t extreme. The intermediate ML size, on the other hand, is an excellent addition as it will make things much easier for all those riders who find themselves between two frame sizes. In general, we like that Trek is offering the Slash in five sizes, thus making an optimal fit available to as many riders as possible.

The geometry at a glance:

An overview of the various slash models.

Trek are offering the new Slash in two aluminium models and three carbon versions. The 9.8 and 9.9 carbon models are further split between versions with a SRAM or a Shimano drivetrain and different colours, including a completely customised paint job thanks to Trek’s Project One concept. Pricing for the new range starts at € 2,999 for the Slash 7. However, the most attractive model for most riders will be the € 3,499 aluminium Slash 8, which leaves little to be desired in terms of its components. The most affordable carbon Slash is the 9.7, retailing for € 4,499. Topping the range is the 9.9 XTR Project One bike for € 9,099. Both the carbon and aluminium frames are available separately for € 3,999 and € 2,499, respectively. Compared to the complete bikes, this doesn’t seem like a very sensible option for most buyers.

A brief introduction of the different models

Trek Slash 7 – your entry into the range – € 2,999

At € 2,999, the Trek Slash 7 is the most affordable model. It comes with a RockShox Yari fork, a Deluxe Select+ shock without a reservoir, an NX Eagle drivetrain, and weak Guide T brakes. Both the suspension and the brakes are compromised and we would recommend paying € 500 more for the Slash 8.

Trek Slash 8 – great value for money – € 3,499

It sounds almost too good to be true – for just € 500 more, the Slash 8 comes with a RockShox Lyrik RC fork, a Super Deluxe Ultimate shock, a GX-Eagle drivetrain and the powerful SRAM CODE R brakes! Functionally, there is nothing to complain about on this bike. Anyone looking for an attractively priced enduro bike to hit the trails at full speed should take a closer look at this model.

Trek Slash 9.7 – your entry into the world of carbon – € 4,499

The Slash 9.7 is the only model in the lineup equipped with FOX suspension. It comes with a 36 Rhythm fork and a DPX2 shock. Shifting is taken care of by SRAM NX and GX components and a pair of SRAM CODE R brakes provide the stopping power. There is nothing to complain about on the bike, but we would personally save ourselves the additional € 1,000 for the carbon frame and spend the money on slight upgrades for the Slash 8 instead.

Trek Slash 9.8 XT or GX – available in Project One on request – from € 5,999

The Slash 9.8 is the most affordable model available in Trek’s Project One range. For a surcharge of € 500 or more, you can get a completely custom paint job. It comes either with a SRAM GX or Shimano XT drivetrain. The SRAM variant is paired with G2 brakes while the Shimano model is specced with a pair of SLX four-piston brakes. We would choose the Shimano option for the brakes. Both models feature Bontrager Line Elite carbon wheels. The suspension is taken care of by a RockShox ZEB Select+ fork and the specially developed Super Deluxe Ultimate shock. In our opinion, if you must have a carbon frame, this is the model to go for.

Trek Slash 9.9 X01 or XTR – also available in Project One on request – from € 8,499

You only want the best? Then you should choose the Trek Slash 9.9. The bike is optionally available with a SRAM X01 or Shimano XTR drivetrain and can be completely customised as part of the Project One concept. The bike’s handlebars, as well as the Bontrager Line Elite wheels, are made of carbon. The suspension consists of a ZEB Ultimate fork and a Super Deluxe Ultimate shock. From a rational point of view, the extra charge compared to the Slash 9.8 simply isn’t worth it – but who of us is rational when buying a bike?

Our review of the new 2021 Trek Slash 9.9 X01 enduro bike

More than six weeks before the official launch of the new 2021 Trek Slash, we were lucky enough to do an in-depth review of the flagship 9.9 X01 model in size L. Besides riding the bike on our home trails, as usual, we also took it to the bike park in Innsbruck. As if that wasn’t enough, we included it in our enduro bike group test, which will be published in the next issue, comparing it to the hottest enduro bikes of the year. In total, the new Slash 9.9 XO1 was ridden by five experienced ENDURO test pilots.

At first glance, the new Slash looks a lot like its predecessor. However, the frame is generally beefier. As soon as you climb aboard, you’ll immediately notice a few differences. The bike is longer, the seat tube angle is steeper and the suspension feels plusher. The riding position is comfortable, neither too stretched nor too upright. However, the seat tube angle remains on the slacker side of the spectrum. Long-legged riders or anyone who regularly attempts very steep climbs will have to push the saddle as far forward as possible. By doing so, we were able to find a suitable climbing position. Riding uphill, the rear suspension is as pleasantly efficient as before, as long as you stay seated and pedal in even strokes. If that’s the case, you can leave the shock open without any problems. However, if you have to get up out of the saddle to pedal, we recommend locking out the shock first. Overall, the Slash is a capable climber and will easily get you to the top of every trailhead.

Let’s be honest – who would buy a Trek Slash for its climbing prowess? If climbing is your thing, you should perhaps take a closer look at the Fuel EX instead. Where the Slash has to deliver is on the descents and once you drop the saddle, you’ll immediately feel that you’re dealing with a completely different beast. While the previous Slash was more reminiscent of a modern, long-travel trail bike with its rather firm suspension and compact geometry, there’s no denying what the new bike was designed for. The suspension responds a lot more sensitively and literally sticks to the ground. The added reach gives you lots of freedom of movement and you’ll feel much more integrated into the 2021 Slash than on the predecessor. When the descents get steep and technical, the bike’s length keeps it very composed, holding its line and generating a lot of traction. Provided that you replace the SE4 rear tire, because it doesn’t do justice to the new Slash in any situation except for its low rolling resistance. On demanding terrain, there is room for improvement with the small 180 mm rear rotor as the SRAM CODE RSC brakes tend to fade quickly. This bike requires at least a 200 mm rotor and is even approved for up to 220 mm versions – excellent!

Just pull up – the Slash easily copes with botched landings!

The rear end of the Slash performs sensitively with just the right amount of progression towards the end-stroke, but we got the impression that it gives up its travel to readily in the medium compression setting, making it wallow slightly in the mid-stroke. The shock offers enough support through compressions, but it’s a little wallowy in general. Installing three volume spacers didn’t do anything to help. We tried different sag settings between 25 and 30%, finding the sweet spot at around 28%. In combination with the long 485 mm reach and the compact 437 mm rear end, the Slash demands a very committed riding style through corners and for quick direction changes. If you don’t get actively involved, you’ll find yourself hanging off the back of the bike and lacking grip on the front wheel. If you set the compression lever on the shock to the plus, the bike offers more support. However, we would only recommend this setting for flow trails as it comes at the expense of small bump sensitivity as soon as you take on more natural trails. We would have liked to be able to fine-tune the shock more. If you’re not sure about the frame size, we recommend sizing down. Looking back, the ML Slash would have been a better option than the L for a rider height of around 180 cm.

What else did we notice while testing?

The handling of a bike is key, but there are a few other factors that are important to consider before buying a new bike. One feature that makes the Slash so attractive for many enduro riders is the additional storage compartment in the down tube. You can use it to store a tube, an energy bar, a pump or simply a packet of gummy bears. Specialized were the first brand to offer this feature on their carbon bikes. Compared to the opening on the current Specialized Enduro, that of the Slash is smaller, but the latch is easier and quicker to open.

Tuning-Tipps: choose a smaller frame if necessary | larger brake rotor at the rear | Swap tires for a grippier, more robust model

There are a few other things we noticed during our test. Unfortunately, the rubber stopper that allows the thru shaft shock to fully compress came loose. It to be fumbled out of the frame. The shaft had also slightly damaged the housing of the shifter cable – no drama, but annoying. Last but not least, the Bontrager Line Elite carbon rims didn’t survive the test unscathed. While riding, we couldn’t remember encountering any hard impacts and the tires were always inflated to the correct pressure, but the rim wall delaminated from the bed. As a result, the tubeless tire would no longer stay inflated.

Our conclusion on the new 2021 Trek Slash

With a series of updates, Trek aim to put the Slash back on the podium. Thanks to its plush suspension and capable geometry, it’s ready to take on the most demanding trails. The integration of the storage compartment, the comeback of the threaded BSA BB and the longer dropper post are great. However, there’s little innovation and the unsuitable tires, the small brake rotor, the still slack seat tube angle and the lack of adjustability on the rear shock cloud the otherwise positive impression of the 2021 Trek Slash 9.9 X01.

• plush suspension
• practical storage compartment in the down tube (also on the aluminium frame)
• composed handling in rough terrain
• beautiful paint job
• additional ML frame size for the perfect fit

• unbalanced in flat and open corners
• minimal adjustment options on the rear shock
• tires and small rear brake rotor don't do the bike justice

More infos on trekbikes.com

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Trek Slash 9.9 RSL Review

Words by Drew Rohde // Photos by Michael Darter & Dennis Yuroshek

When Waterloo, Wisconsin based Trek Bicycles revamped their mountain bike line for 2017 a lot of people took note. For several years Trek offered their three dual suspension bikes – the Fuel EX, Remedy and Slash in various wheel sizes. Trek’s current offering now aligns itself with current trends in the ever-changing (10mm at a time) landscape of mountain bikes. The Trek Slash, which was once considered more of a freerider’s bike is now squarely aimed at the enduro race crowd with its 29-inch wheels and 150mm of rear wheel travel and a 160mm fork. We tested the flagship 9.9 RSL (Race Shop Limited) build, which sports heavier duty tires and the most performance-minded build for discerning riders.

Over the last decade, Trek has quickly gone from being your dad’s bike brand to a company with an esteemed pedigree. Starting with Aaron Gwin’s World Cup domination aboard early Session frames to the Atherton’s current Session 9.9 dream machines. Tracey Moseley has amassed EWS victories and Trek also sponsors what is arguably the most impressive freeride roster, the C3 program.

The Slash’s geometry is adjustable via Trek’s Mino Link and is definitely worth praising as the bike feels very well balanced and stable regardless of the position we flipped the Mino Link to. In the high position the Slash has a very capable 65.6-degree head angle with a 64.8-degree seat tube angle and 13.86-inch BB height. The reach on our size large 19.5-inch frame was 18.07 inches with a 47.99-inch wheelbase and 17.04-inch chainstays.

The spec on the 9.9 RSL is a bit of a mixed bag. Fox Factory shocks handle the bumps but aren’t our favorite offerings from the brand. Trek chose to spec this enduro-ready racer with a Talas fork, which does not work as well as a Factory Float without travel adjust. The performance penalty for a non-essential feature is not worth it in our opinion. Out back a Float X2 shock also gave us a bit of trouble as we feel this damper lacks the ability to quickly open up on chattery, small to medium-sized obstacles based on our experience with several other bikes also spec’ing this shock. Trek’s tune further exacerbated the shock’s weakness as we ended up having to use the maximum number of volume reducers to find the sensitivity we wanted yet still had issues bottoming out too easily. We contacted Trek and requested a Rock Shox Super Deluxe to compare it to because we had one on a Trek Remedy and absolutely loved it! After back-to-back experimentation and one last phone call with Jose Gonzalez, Trek’s suspension guru, we gave the Fox another go. With the maximum number of volume spacers (5) installed and a change in air pressure, both front and back we found our happy place. That said, we worry about riders who are heavier and faster than our 170lb hacks as we still reached bottom several times on fast runs with 5 spacers installed. Depending on your weight, riding terrain and style, this may or may not be an issue for you.

SRAM’s Eagle drivetrain held up to a real beating on the Slash and never skipped a beat. It always shifted and pedaled like a dream. The SRAM brakes left a little to be desired in terms of lever feel and power but they got the job done. What didn’t get the job done however was the Bontrager dropper post. It gave up the ghost pretty quickly, which to be honest wasn’t a huge bummer as the 125mm of travel was really cramping our style on the steep descents of the PNW. The rest of the cockpit and wheels held up great and we’d have no problem recommending any of those parts for hard charging.

As we mentioned above the initial set up on the Slash had us a bit discouraged since the Rock Shox-equipped Remedy instantly blew our minds as one of the best bikes we’d ridden. Some diligence and that last motivational call to Jose paid off however as the bike blossomed into a fiery red butterfly. The capabilities of the Slash impressed all who rode it. While it may sound like we’re coming down a bit hard on the Slash, and perhaps we are, the reality is, hands down, the Slash is one of the best bikes we’ve ridden. As time progresses however, bikes continue to improve and brands always creep up the ranks. In order for reviews to rise with the tide of these awesome new bikes, we need to increase our pickiness. It’s time to really flush out the little stuff, since that’s kinda all we get to complain about now that nobody specs triple chainrings or 90mm stems and 720mm bars.

The Slash 9.9 got passed around like a joint at a Cypress Hill concert. In some instances we’d even hop off and hand it over mid-run. It was a pretty eye-opening experience to be ripping on a bike we got along with pretty well only to throw a leg over the Slash and feel like we just unlocked a super power. Speeds increased, cornering confidence went way up and traction gains only made us feel like pushing harder. Our testers enjoyed the Slash in fast terrain with lots of turns and chunder. It’s clear that this bike was designed to move.

the Slash had us a bit discouraged since the Rock Shox-equipped Remedy instantly blew our minds as one of the best bikes we’d ridden. Some diligence and that last motivational call to Jose paid off however as the bike blossomed into a fiery red butterfly.

The wolf’s last word.

The bike is flat-out fast! Whether we were screaming down 6-inch wide ridgelines or scratching down steep, rugged DH tracks, the Slash was all in. We’ve spent a good amount of time aboard all three of Trek’s offerings and surprisingly, the Slash feels less like a 29er than it’s shorter travel brother, the Fuel EX. On only the steepest of chutes did we bump our ass on the tire. The dreaded rear wheel hang up that some 29ers experience going off slow speed drops was never an issue on the Slash.

Of all places we rode the Slash, we noticed it excelled in the corners and at high speeds. The confidence to attack turns is pretty heroic. It’s hard to pick a weakness in terms of on-trail performance as it really didn’t do anything poorly, once we finally got the set up dialed that is. Our biggest issue was with the Fox spec and shock tune. The Talas fork doesn’t perform as well as it’s Float counterpart and the shock tune is lacking for aggressive or heavy riders. At roughly 170 pounds our testers relied on the maximum number of 5 volume reducers to offer the ramp up needed while trying to keep the air spring and compression sensitive enough for trail chatter. Despite our critiques above, the Slash 9.9 is one of our top three all mountain bike choices this year. We’ve spent several months aboard similar bikes in the category from the Rocky Mountain Slayer to the Norco Range and Trek slashes the competition in the all-mountain category with this machine. A little patience and experimenting will help you and the bike achieve a new level of riding.

Price: $7,999

Weight: 29.79 lbs

Sizes: S, M, L, XL

Website: trekbikes.com

CHASSIS Frame: OCLV carbon; 150mm Fork: Fox Factory 36 Talas; 160mm Shock: Fox Factory Float X2; 230 x 57.5

COCKPIT Brakes: SRAM Guide Ultimate Handlebar: Bontrager Line Pro; 780 Headset: FSA Knock Block Saddle: Bontrager Evok Ti Seatpost: Bontrager Drop Line; 125mm Shifter: SRAM X01 Eagle Stem: Bontrager Line Pro; 35mm

WHEELS Hubs: Bontrager Line Elite Rims: Bontrager Line Elite 30 Tires: Bontrager SE4 Team Issue; 29 x 2.4

DRIVETRAIN Bottom Bracket: SRAM PF92 Cassette: SRAM XG-1295; 10-50t Cranks: SRAM X01 Eagle; 32t Derailleur: SRAM X01 Eagle; 12s

Looks Comfort and Confidence Versatile

We don’t, bontrager post fox x2 shock and tune talas fork.

• Slash 9.9 XTR Gen 5

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Winner - Mountain Bike category

"The combination of high-end performance with individuality and user-friendliness in the thought-through package delighted the entire jury."

"Feels exactly right"

"The Slash has a big-bike feel that makes it easier to charge into an unfamiliar trail, while retaining enough maneuverability to prevent it from feeling like overkill on mellower trails."

Enduro Bike of the Year

Once the dust had settled, it was the Slash that managed to edge its way into the lead. Its ability to tackle the wildest terrain without flinching yet all the while retaining that reactive, lively feel really won us over.

"A hell of a bike"

"Slash is great on rough, bermed corners and it has been an absolute monster riding steeps. This is an easy bike to ride and everything felt very natural from the first drop in and I haven't looked back since."

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