trek slash 9.9 xo1

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.

Mountain Bike Magazine

[Tested] 2021 Trek Slash 9.9 XO1

It’s been quite some time since Trek last updated the Slash – four plus years ago to be a little more precise. Since the last iteration was released, there have been enormous changes in the trends popular amongst bikes in the Enduro category. Perhaps the biggest refinements have been to geometry, and unsurprisingly the new Slash has undergone major tweaks in that arena. With that said, the bike also sees a plethora of other updates such as the inclusion of downtube storage, a radically different rear shock, a 10mm front/rear travel bump and a host of other subtle and not-so-subtle changes. For the last few weeks I’ve been getting to spend a great deal of time on the new bike at Silver Mountain in Idaho. Rough and ragged with descents nearing 4,000 vertical feet per lap, Silver has made the perfect testing ground for the hungry new Slash. Read on to see how it’s been working out…

• 29″ wheels only
• Boost front and rear hub spacing
• Metric shock sizing with trunnion upper mount
• 170mm front travel / 160mm rear travel
• ABP (active braking pivot) suspension layout
• Mino-Link flip chip for adjustable geometry
• SRAM Universal Derailleur Hanger
• Internally routed cables / hoses
• Knock Block 2.0 with increased turning radius
• Downtube storage
• Full downtube protection
• 32 pounds (tubeless, no pedals)
• $ 7,999.99 USD

Starting with suspension, up front we see the all new RockShox Zeb with 170mm travel and a 44mm offset crown. With burly 38mm stanchions, the fork feels nearly as stiff as a BoXXer double crown fork. Like most RockShox offerings, it has externally adjustable high and low speed compression with a single rebound adjuster via its Charger 2.1 cartridge. An all new industrial design, the option of an integrated fender and a bottom out indicator are a couple of other new features.

We could dedicate an entire story to the new rear shock but we’ll try to keep it brief. Gone is Re:Aktiv, a technology co-developed with Penske to improve pedaling performance. Thru-Shaft still remains, and this new version of the shock is based around a RockShox Super Deluxe Ultimate. Okay, so – Thru-Shaft offsets shaft displacement by having the shock’s shaft literally exit through the bottom of the shock as it cycles through its travel. This means that the shock’s reservoir and thus its internal floating piston are now mainly concerned with temperature management as opposed to also dealing with shaft displacement. In lieu of Re:Aktiv, is a standard shimmed damper (Hallelujah!) which now has a simple 3-position adjuster to help tune out pedal input. It’s not really an open / trail / lock style setup, but rather three broad settings of low speed compression. This adjuster controls the extent to which a shim blocks an orifice that manages low speed compression on both the compression and the rebound side, and thus helps mitigate pedal bob cause by both compression and extension. More on the rear shock under “Setup”…

A handful of features, both new and old. Clockwise from top left: KnockBlock 2.0 features a warmly welcomed increase 14º in steering radius, from 58º to 72º. It also no longer needs the frame bumper of old on the downtube. Much like the new Fuel EX, Trek has included downtube storage via a trap door under the bottle cage, which is a life saver all around. Like most Treks, the new Slash features Mino link, a flip chip that offers a .5º variance in head tube angle and a +/- 7mm adjustment to bottom bracket height. Lastly, Trek have also jumped on the bandwagon of stashing a multi tool in the steerer tube. Compared to the Specialized SWAT CC that this is seemingly modeled after, it does offer an expanded range in tools and an improved chain tool, although it is a pain to install and remove the unit as a whole.

SRAM’s reknowned X01 Eagle 12 speed group is standard fare, albeit now with an expanded range due to a bump from 50T to 52T in the largest gear. Up front a 30T is spec’d to motor you up the big climbs on long days, and an MRP chainguide protects your investment. One thing we found odd is the choice of 175mm length cranks – on a bike this aggressive, we would have expected and very much preferred shorter 170mm cranks. Aside from that, much like we’ve come to expect over the last couple of years, the Eagle group has offered phenomenal shift quality and a huge range.

Up front, it’s mainly in house spec, starting with Bontrager lock on grips which were swapped for our trusty Sensus Meaty Paws. The handlebar itself is a crazy wide 820mm Bontrager Line Pro carbon fiber bar. It has a 35mm clamp and a 27.5mm rise. I trimmed the bar to 800mm, which was easy due to its guide marks. Lastly, the Bontrager Line Pro stem meshes nicely with the Knock Block system, although that does leave you relegated to 10mm bar height adjustments. Feeling like my hands were resting a bit too far behind the front tire’s contact patch, I switched the stock 35mm length stem for a 45mm and felt at ease right away.

The latest version of Bontrager’s in-house dropper post has been exceeding expectations. Its action is smooth and it is stiff and supportive, due to the oversized 34.9mm diameter. As far as the lever goes, at first it seemed odd that it is placed so close to the handlebar, but I eventually took to it and realized that it helps you keep a better grasp on the grip when actuating it. The Arvada saddle had a good silhouette and just the right amount of padding, although it doesn’t seem to be all that rugged. All in all though, no complaints.

As one of the more high end models, we were happy to see Bontrager’s Line Elite 30 wheels spec’d on this model of the Slash. The 29mm inner diameter carbon fiber rims have seen an updated profile that is a bit shallower to help take the edge off and give them a smoother ride quality without compromising stiffness. Thicker rim walls provide better impact resistance while the 108 point engagement provides fast power transfer. As far as tires go, the SE5 / SE4 combination are decent tires, but I don’t feel they are up to the task that the bike is clearly capable of, on the whole. The bulk of my testing was spent on Schwalbes with thicker casings and a burlier tread pattern. Speaking of tread pattern, it’s been some years since we’ve seen anything new from Bontrager and in my opinion, they are past due…

Last, but certainly not least, SRAM Code RSC brakes are tasked with slowing things down. These are my brake of choice on my personal bikes and I can’t say enough good things about them. The 200mm front and 180mm rear combo bolts up nicely with no adapters and gets the job done. Hard chargers who frequent steep terrain and/or long descents may want to swap up to a 200mm rear, but in stock form they should be just right for most riders.

While the new Slash sees a slew of new developments, the geometry updates are substantial to say the least. First off, the size range gets expanded from four up to five size offerings. The chainstay length hasn’t changed much, but the head angle has slackened one full degree and the BB dropped by a few millimeters. Speaking of angles, both the virtual and effective seat tube angles have been made steeper by a two full degrees for improved climbing. Lastly, reach numbers grew by roughly 25-30mm depending on the given size. All in all, the new Slash is a much more up to date bike with aggressive, but not ground breaking, numbers all around.

Starting with suspension, I began at my usual 20% sag up front and 30% sag out back, and to be quite honest I never once looked back because I was never compelled to. Straight out of the box, the suspension curve and progression rate was dead on, so aside from playing with rebound and the compression settings a tad, I never felt the need to add or remove volume reducers at any point. Keeping  that in mind, this new version of the RockShox Super Deluxe with Thru-Shaft allows for one further element of adjustment – you can run zero or one negative air spring reducer, should you choose. This will essentially affect your off the top feel, being softer or firmer, respectively. Speaking of air springs, the new air can features a negative air spring volume that lands roughly between the standard Super Deluxe air can and a MegNeg – at least according to Chris Mandell at RockShox. On top of that, t he all new shock has some very interesting features – some of which could provide a glint into future products from RockShox. T he rebound dial is now numbered, and for what it’s worth I found myself right in the middle at the number 5 setting, which is spot on for a 180 pound rider. As far as cockpit goes, it was easy to get all dialed in with a longer 175mm travel dropper seatpost on my size Large, but I did wish I could have raised the handlebar a bit higher. Trek ships the bike with two 10mm spacers that are integral to Knock Block. For the taller, lankier riders out there it would be nice to see the steerer tube cut a little longer so that 3 spacers could fit. This means that I’ll need a taller bar or stem if I want to go any higher – a small matter, but worth mentioning.

On the trail

When testing a new bike, my initial saddle time is almost always spent on a climb as most of my time on the bike is pedal powered. With the Slash however, I was fortunate to squeeze in a great deal of descending (roughly 75,000 feet of vertical) in very short order, thanks to the fact that I now live just 40 minutes from Silver Mountain. Dropping into the upper trails you’re greeted by loads of super sharp rocks that are both loosely strewn about and firmly embedded into the dirt. As the trails dip down into the woods, as you’ll see in the video below, there are loads of roots, braking bumps and bomb holes. So while the area I tested in is plenty rough, it isn’t all that steep – not Santa Cruz loamer steep anyway. Silver’s borderline excessive mid-grade bench cuts and off cambers will make a full DH bike feel difficult to muscle around at times, but duty wise, the Slash turned out to be just right for this type of riding. So, how did it go?

Well, straight away, up front I was very impressed by the Zeb and this was actually my first time aboard one. It felt very familiar as its Charger 2.1 damper makes the action feel a lot like a Lyrik or a Pike. The air spring’s lower operating pressures, which I was able to run in the 60 PSI range as opposed to the 90 PSI range, improved sensitivity. Perhaps that could also be attributed to its burly chassis, which definitely wowed me in terms of stiffness and steering precision. Getting to the frame itself, out back I’ve got to admit – I was never really a big fan of Re:Aktiv and I’m happy to see it gone. Its hydraulics interfered a bit too much as it tried to create the perfect bike that climbed like a hardtail without needing to lean on a lockout. To me, it always seemed gimmicky and inhibited the flat out performance as the pedal platform never quite “got out of the way” enough in the rough stuff. This is absolutely NOT the case with the new rear shock, which has totally won me over.

Now, before I continue heaping on praise of the rear shock, it’s worth pointing out that on the kinematic side, Trek’s engineers have also done their homework and done it well. I’ve always felt that ABP has been one of the most compliant feeling layouts on the market, especially under heavy braking, and on the kinematic end it shines brightest in successive mid sized events such as babyheads, chunder, roots, braking bumps, etc. This bike carries on that tradition and does it better than ever before. With past Trek models that used Re:Aktiv, after just one ride, I often found myself pondering if it would fit a coil rear shock, hoping to get more compliance out of the actual shock itself. With the new Slash I never once felt the need for a coil, even on the aforementioned brutal 4,000 foot descents. So, this new RockShox Super Deluxe with Thru-Shaft sure seems like a whole new air shock altogether from RockShox. Regardless, the action was excellent with bountiful traction, plenty of control, just the right air spring curve and a nice range of usable adjustment both on the hydraulic and pneumatic side.

It’s worth discussing the new Low Speed Compression switch (in blue) for a moment. When doing park laps, I left it in the most open of the 3 positions and got all the traction I could ever ask for. Initially I started out doing laps in the middle setting and every so often I got the odd, perceptible spike now and again when transitioning from smooth sections to a first initial impact. I personally found that although the variance between the 3 settings is nowhere near as extreme as an “Open, Trail, Lock” style lockout, I preferred to use this lever in the same fashion. When descending for long periods of time, I left it fully open. When grinding up long climbs I left it in the *almost firmest setting – which by the way feels pretty compliant but pedals very efficiently. Note the shock has a totally firm lockout via the two-position black lever, I tested it out but never used really it – surely riders will appreciate it on fire roads though. Anyhow – on variable trails I just left it in the middle position. Lastly, I liked that the adjuster sits at 45º on the shock body, which makes it easy to reach while riding. Left handed riders will like it even more based on its position.

Okay, so the suspension flat out rules. What about geometry, handling, features and all the other important stuff? Beginning with the former, I actually started out and hardly strayed from the higher / steeper geometry option due to the longer 175mm cranks. While I can’t fault the ride quality in this setting, I could certainly see myself and others taking advantage of the lower / slacker option on steeper and faster terrain, so it is great having the option, but I would personally prefer to go down that road with shorter cranks. On the whole, the Slash has made leaps and bounds and landed right about where a modern Enduro bike should be, geometry wise. The front:rear center length ratio is just right, making it well balanced front to back. The bike is easy enough to manual and get around tight corners, but doesn’t give up much in terms of stability. The head angle is just right – a bit more nimble and sprightly in the high position. In low/slack it is detuned and desensitized to speed a bit more, but does flop a touch more on the climbs, which is to be expected.

If I had one complaint it was that, although Trek steepened the seat angle by 2º, in my opinion they could have taken that further still, to make for a bike that puts your body in an even better position to grind out climbs all day, regardless of the fact that you’re basically on a downhill bike. A ~75.75º (average) effective seat angle is nothing to scoff at, but I’d love to see it more like 77º. Then again, I’ve got long limbs and a short torso, and riders with opposite and/or more average proportions won’t be as phased, because they won’t require such a tall seat height and thus will sit further forward.

In terms of the overall handling, I can’t think of a single negative attribute. This is partially credited to the aforementioned geometry and suspension, but also a nod is very much due to the frame’s excellent layup and construction, which makes it just rigid enough without riding rough, and helps it boost when you need to get it off the ground. Despite being a long travel bike, Slash assertively walks the line between surefooted confidence and a sprightly, poppy demeanor. It’s easy to both hold the line and change the line in a millisecond. I went into this review thinking it would feel like a lot of bike, but it didn’t. At 32 pounds it’s actually pretty light weight when you consider just how much bike this is, and that it picks up roughly a pound from its full coverage chain guide – something that also earns the product managers the tip of a hat.

Regarding spec, for the most part I think Trek has done a stellar job at picking out a good mix here. The Zeb fork is a standout and both the Eagle drivetrain and Code brakes have earned high praise from us over the years, so I won’t drone on about them. Grips aside, the cockpit leaves little to complain about despite being fully in house parts from Bontrager. I quite liked the revised dropper post – it was smooth and less flexy on the climbs due to the oversized 34.9 diameter. The wheels have proven, like their slightly more expensive counterparts , to be really damn good. I had more than a handful of scary rock to rim impacts that had me pulling off trail to assess the damage, only to find none. Central to wheels, there was the issue of tires which I went over in “Details” – simply put, more aggressive riders will likely want to swap them out on short order.

As far as the noteworthy Trek/Slash specific features go, I will say that these days I’m much more of a fan of Knock Block than I once was. First and foremost, with the increased turning radius, now you straight up don’t even notice it. In fact if you do notice it while riding, it means you’re likely just about to hit the deck. And this is where it’s most beneficial. Since my first time riding Knock Block about 4-5 years ago, I have had one rather dramatic crash which resulted in a split brake line on a bike without Knock Block – the brake line split from the bars spinning too hard without a steering stop. On my very long walk home I spent a great deal of time talking to myself and thinking that maybe Knock Block isn’t that bad after all. In terms of the downtube storage, it’s obviously brilliant – in fact, it makes it very hard to go back to other systems where you’re relegated to stashing odds and ends on your bike.

So, aside from a couple of minor grievances – long cranks, flimsy tires, seat angle could be *slightly* steeper – the Slash is a super impressive machine. Every single attribute has been greatly improved over the past model. It’s very manageable for long days in the saddle with big climbs, but where it shines most is when things get rough…really rough. It absolutely gobbles up impacts of all speeds and sizes flawlessly. Both front and rear it was supple, sensitive and full of traction. It’s near impossible to get it to misbehave in the successive mid-sized hits, and on heavy impacts I used all the travel often and the o-rings just kissed the bottom out indicators – but I never felt one single harsh bottom out. It was the suspension performance above all that impressed me, and the handling came in at a close second. Sprinkle in smart features like downtube storage, Knock Block plus little things like the shuttle guard and you have a winner.

In my closing thoughts I always factor in value and yes, $7,999 is a lot of money for a bike, but it’s par for the course when it comes to flagship spec, and this specific model features a damn good parts pick, with carbon wheels and no major corners cut. If this model would leave your wallet too light, just know that there is a full range of new Slashes at a wide array of price points and aluminum frame options – consider the Slash 8, which packs an amazing punch at $4,000. Last but not least, props to Trek for including the downtube storage feature on those aforementioned metal models as well. All in all, the Slash is a bike park monster and would be an excellent candidate for a privateer racer as well. You’d be a fool not to consider one if you’re in the market for a new Enduro bike.

www.trekbikes.com

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Trek Slash 9.9 X01 on test – How will the icon fare in the fight against the clock?

Apart from the name and the similar design of the frame, the new 2021 Trek Slash doesn’t have much in common with its predecessor. It’s longer, slacker and plusher. But is it also faster? We were very excited to be given the exclusive opportunity to test the bike on our race stage before its release.

In our introduction of the fastest enduro race bike on test you can’t just find our most interesting findings and our overall conclusion, but a good view on all bikes tested.

The brand new 2021 Trek Slash was developed in close collaboration with Trek’s enduro racing team and other athletes. This quickly becomes clear when you look at the geometry and the suspension. However, those athletes obviously weren’t as involved in choosing the components: the Slash comes fitted with a small 180 mm brake rotor at the rear and rolls on Bontrager trail tires, which lack the grip and puncture protection needed for enduro racing. For our test, we replaced them with a set of grippy Schwalbe tires fitted to aluminium DT Swiss wheels that we swapped for the stock carbon option.

We also shortened the overly wide handlebars on the stock build from 820 mm to 780 mm. That aside, there’s not much to fault on the rest of the build. The massive RockShox ZEB suspension fork offers 170 mm travel, while on the back, the Thru Shaft Super Deluxe, uses a design developed by Trek in cooperation with RockShox and promises to respond extra sensitively. The SRAM CODE RSC brakes are there to keep your speed in check. The cockpit and seat post are supplied by Bontrager.

Trek SLASH 9.9 2021

Specifications.

Fork RockShox ZEB Ultimate 170 mm Rear Shock RockShox Super Deluxe Ultimate 160 mm Seatpost Bontrager Line Elite Dropper mm 170 Brakes SRAM CODE RSC 200/180 mm Drivetrain SRAM X01 30 (10-50) Stem Bontrager Line Pro 40 mm Handlebar Bontrager Line Pro, OCLV Carbon 780 (820) mm Wheelset Bontrager Line Elite 30 OCLV Carbon Tires Bontrager SE5/SE4 2.6"/2.4"

Technical Data

Size S M ML L XL Weight 14.7 kg Wheelsize 29"

Longer, slacker, steeper – the geometry of the 2021 Trek Slash

While the previous Trek Slash had started to seem more like a long-travel trail bike in recent years, the new Slash has been brought back to full enduro. Trek have given the size large a long reach of 486 mm. The chainstays are kept short at 437 mm and the 64.1° head angle is plenty slack. In theory, you could adjust the geometry using the Minolink flip chip but since the bottom bracket isn’t that low, even in the slack position (29 mm bottom bracket drop), we didn’t make use of this option.

The steeper the better! With its geometry, the Slash performs best on steep descents.

Super plush – the 2021 Trek Slash on the trail

The new Trek Slash scores right from the start with its super plush and capable suspension. The rear end sensitively irons out bumps and thus delivers tons of traction. However, despite having set up the sag correctly, the suspension tends to wallow. In combination with the long front triangle and the relatively short rear end, this places you far back on the bike and you have to actively shift your weight forward when cornering. The bike does a great job of instilling you with confidence on steep terrain. When it comes to carrying as much speed as possible through a corner, its length is more of a hindrance. With all your weight at the back, the front wheel is light and therefore lacks precision, meaning you’re less likely to hit all your lines accurately.

Does it always have to be longer? Not with the Slash. If in doubt, we recommend the smaller size.

At high speed, the Slash is a force to be reckoned with thanks to its plush suspension and composed handling. Even so, there’s enough mid-stroke support to allow you to generate speed over rollers or get airborne. If you find yourself between two frame sizes, we recommend choosing the smaller frame size of the new Slash. All the better that Trek have decided to offer an intermediate M/L size with a reach of 469 mm. Paired with the super capable suspension, you’ll get a more agile but still sufficiently composed bike.

How does the Trek Slash 2021 compare to the competition?

Trek Slash or Specialized Enduro – it’s been an ongoing debate ever since Trek presented their first 29er enduro bike. At the models in this test, both brands still show room for improvement in terms of the componentry. In terms of handling, the Enduro is slightly more composed and easier to ride in general, while the Trek is more agile in tight sections. However, neither of them proved to be fast on our race track. They’ll do best in the bike park.

Differences from the standard bike

• aluminium DT Swiss wheels
• Schwalbe Super Gravity tires

With its capable suspension and longer geometry, the new Trek Slash is ready for the world’s roughest trails. It instils you with confidence and generates maximum traction on steep terrain – assuming you’ve upgraded the tires. On our race stage, the bike would have been able to perform better if we had had a smaller size, allowing us to carry more speed through corners. Therefore, be careful when choosing the frame size!

• plush suspension offering lots of traction
• practical storage compartment in the frame
• very composed and confidence-inspiring on steep slopes

• requires an active riding style
• standard spec isn't race-ready
• lack of compression adjustments on the rear

Mehr Informationen findet ihr auf trekbikes.com

The testfield

A lot more mtbs, our findings and the trends for the upcoming saison can be found in our introduction of the fastest enduro race bike on test .

All bikes in test: Canyon Strive CFR Jack Moir Edition (Click for review) | Commencal META AM 29 (Click for review) | GT Force Carbon Pro Martin Maes Edition (Click for review) | Lapierre Spicy Team (Click for review) | Nukeproof Mega 290c RS Team Edition (Click for review) | Raaw Madonna V2 FOX Factory Custom (Click for review) | Specialized S-Works Enduro Team Edition (Click for review) | Trek SLASH 9.9 2021 | Yeti SB150 Team (Click for review) | YT CAPRA Elite 29 (Click for review)

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TREK SLASH 9.9 XO1 LONG-TERM REVIEW

Forward thinking slash with new shock technology.

Words by Mike Wirth/Gooseworks Photos by Jon Coulthard

Our season of bike tests with the new Trek Slash was supposed to include a summer of burning laps at the bike park, utilizing the comforts of a chairlift to feed our gravity habit. With bike park operations varying greatly due to COVID-19, and shuttle rides feeling risky with or without masks, we had the chance to test Trek’s new long-travel enduro race machine as it was designed to be ridden, as an enduro race bike with gravity chops that can still be used to climb. We pedaled this bike to the top of every mountain surrounding the Los Angeles area, and then pointed it down the gnarliest lines we could find at least twice a week for the last few months.

THE LAB We won’t delve too deep into the lab in this review, as we covered alot of the major changes and updates to the Slash in our First Ride Report a couple months ago. The new Trek Slash gets a 10-millimeter bump in travel from last year’s version, now sporting 160mm in the rear, and 170mm in the front. Geometry changes follow the “longer, lower, slacker” line of thinking, but still not so far as to call it “extreme.” The frame still has Trek’s Knock Block headset system to protect the top tube and cables in a crash, but the fork crown does clear the downtube, so Knock Block is removable on this year’s Slash. When asked why they went this way, Trek simply said that the feature is polarizing on whether the protection worth limiting steering range. So they leave it up to the rider. Other nice features include internal frame storage for every model, including the alloy ones. A new and larger 34.9mm diameter seat tube accommodates more robust dropper posts. The BSA 73mm threaded bottom bracket is easier to service and less creaky than press fit versions. Something mechanics and tinkerers like myself are very happy about. A full-length downtube guard provides added protection, especially for shuttling, which is another awesome feature.

GEOMETRY CHANGES INCLUDE • Head tube gets 0.6 degrees slacker (high: 64.6, low: 64.1) • Seat tube angle gets almost 2 degrees steeper (high: 76.1, low: 75.6) • Reach gets longer by 20-30mm depending on size

THE DIRT The size XL (21.5”) test bike feels on the big side compared to extra larges from some other brands, which should make all you “Longer is better” folks happy. The 2021 version of the Trek Slash gets a slightly longer top tube, and is paired with a slightly steeper seat tube angle that hides some of this length. Overall, the position is quite well balanced with a position that’s upright yet aggressive.

CLIMBING: RockShox and Trek Bicycles have designed the RockShox Super Deluxe with several options for effective ride settings. For long grinds and fire roads, the switch can be flipped on, which leaves the rear suspension very firm. This puts the rider in the most efficient position with the shock high in its travel and the rider weight forward. Suspension movement is minimal and helps deliver the most power. For more technical climbs, the switch can be flipped open to activate one of three additional compression modes. The “Open” setting is simply too soft for most climbing applications. However, Trek has done a nice job making the other two modes effective for keeping the suspension moving and improving traction on loose terrain. The “+” setting is the firmest of these “Open” shock modes, and keeps the rider higher in the travel while still allowing it to flutter over trail chatter and keep the tires hooked up. Whether you like to set and forget, or reach for a switch every time the trail points up, the Slash has a setting for that.

DESCENDING: The same shock modes that leave options for the climbing modes make for three distinct personalities descending with the Slash. However, no matter where the shock is set, the rest of the bike is built for speed on the descents. The capable geometry beg the rider to push the envelope on hairy descents. We found confidence to hit chutes and steeps our first ride out that have given us pause on lesser bikes. The stable nature of the Slash has a calmness when the terrain feels unforgiving. It’s like riding the back of a Grizzly bear as it powers through the forest. Riding the Trek Slash makes the hardest features feel easier. It almost seems to nudge your eyes to look farther down the trail than you think you need, because you don’t realize how fast the suspension is gobbling the obstacles beneath you and how much sooner you’ll be at that rock or root way down the trail.

I had most recently been spending time on a Yeti SB150 and found that the Slash descends with much more confidence, granted it couuld be the extra bit of travel and shock tune, but when it came time  to point the Slash downhill it was steps ahead in terms of speed and confidence. Although the Trek Slash feels like a massive bike in almost every way, it is in no way sluggish. It’s quite amazing that even the XL we tested rides as snappily and lively as a much smaller, shorter travel bike. With the shock set to the firmer “+” or “O” modes, the rear suspension firms slightly and becomes more flickable. These are the settings we used on jump and berm trails. Testers noted the added support gave the bike a responsive feel that gave plenty of pop off jumps and came off the ground easily to hit the little jib features along the way. With these two modes, the bike feels remarkably playful and accelerates quicker when pumping transitions. With the rear shock set to the softest “-“ setting, the Slash’s suspension becomes much more plush and easy to activate. This setting keeps rider weight low and back, and works best on gnarly, steep terrain. With the shock set to this mode, the Slash is remarkably supple over small and medium hits with solid mid stroke support. The bike digs deep into the travel on big hits and matches the RockShox Zeb fork up front.

MINOR GRIPES: The included multi tool comes with a fairly standard array of tools. It fits neatly inside the steerer tube, out of sight but not out of reach for a quick trailside repair. The stubby bits can be difficult to use, and proved too short to easily use them on bolts that are even slightly recessed, like the bolts on a SRAM Code brake that’s rubbing.

Our first ride out had us second guessing Bontrager SE5 Team Issue tire spec. They sport a a relatively lightweight sidewall that accelerates quickly with impressively low rolling resistance. However, we quickly pinch flatted the tire and ripped a sidewall on a rock that didn’t look overly menacing. Call it first ride bad luck, but we increased our pressure from 24psi to 28 for more insurance. The rounded profile is predictable and provides a nice bite when cornering, although it’s not as responsive as a more squarely-profiled tire. Straight braking traction is ample, though, and the Slash makes the most of the knobs to eek out every bit of handling prowess. Running the tires with lower pressures and a foam liner to provide support the sidewalls might be the secret here.

What may be a gripe here is actually Trek’s reaction to forums so we can’t fault them too much there. The 820-millimeter Bontrager bar is massive, and will need to be cut down for most riders. Even on our size XL test bike, we cut our bars down to 790, but it’s nice riders have the option.

We had shock mount bolts come loose twice during a season of testing. The rest of the hardware performed impeccably. The bottom bracket started creaking on us a couple times during the season, likely from too many stream crossings and bike washings post rides. The threaded bottom bracket makes servicing that area much quicker and easier than a press-fit BB. We applaud Trek for this spec. The bearings in the BB and the frame are still smooth after a full season of hard riding through creeks and SoCal’s grease-eating dust.

The Wolf’s Last Word

Back in the day I always imagined a “unicorn bike” as being an anorexic DH bike built with parts so light it floated uphill easily and then smashed downhills like a gorilla. Lucky for us, bikes have evolved beyond our childhood dreams and now we can have our cake and eat it too. The Trek Slash has a supreme capability to make climbing absolutely bearable and fairly efficient, which is impressive for it’s travel and capability on the downs. Trek’s new Slash has descending chops that rival any long travel bike we can think of. During this unusual year when no chairlifts were available to test, this Slash became the most effective tool to access gnarly trails, with its sort of “portable chairlift” feel.

Price: $7,999 Website: Trekbikes.com

SPECIFICATIONS

CHASSIS Frame: OCLV Mountain Carbon (160mm travel) Fork: RockShox ZEB Select+, 44mm offset, (170mm travel) Shock: RockShox Super Deluxe Ultimate Thru Shaft

COCKPIT Brakes: SRAM Code Shifter: SRAM X01 Handlebar: Bontrager Line Pro Carbon (820mm) Headset: Knock Block 2.0 Integrated Stem: Bontrager XR Trail (35mm) Saddle: Bontrager Arvada Seatpost: Bontrager Line Elite Dropper

WHEELS Wheelset: Bontrager Line Carbon 30 (29”, 54t driver) Tires: Bontrager SE4 Team Issue

DRIVETRAIN Bottom Bracket: SRAM DUB Cassette: SRAM X01 (10-52t) Cranks: SRAM X01 Derailleur: SRAM X01

Excellent geo that’s progressive without being extreme Effective and easy to use shock tune RockShox Zeb fork and build kit are up for a challenge Finish quality on paint, hardware and house brand components top-notch

We don’t, slashed sidewall on bontrager se5 tire sram code brakes impossible to adjust with included multi tool, and they require adjustments, leave a comment | win free stuff.

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• Rider Notes

2019 Trek Slash 9.9

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

For This Bike

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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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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.

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

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Seat tube angle could still be a bit steeper

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

Sept 2020 · Alan Muldoon

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

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.

After making an unofficial appearance last weekend at the Enduro World Series event in Zermatt, Switzerland, the latest incarnation of the Trek Slash was officially unveiled Wednesday. On paper, the new 29er rock smasher looks to be more capable than its predecessor, boasting a bump in rear suspension travel from 150 mm rear/160 mm front to 160 mm/170 mm.

Trek is ready to unleash the new Slash, which gets more travel, a more practical frame design and a very special rear shock. We've been testing the 2021 Trek Slash 9.9 for the past month, and it turns out this ain't no one-trick pony. Read on for everything you need to know about the new Slash.

Wickedly supple and sensitive suspension

Super stable in steep and rough terrain

The playful, agile attitude

Generous frame protection

Stealthy quiet on the trail

Downtube storage could be more generous

We'd like to see a slightly steeper seat tube angle

Jun 2019 · Steve Solt

This 150/160mm aluminum 29er features trail handling and enduro travel.

May 2019 · McCoy

Economy-class enduro

The Slash 29 didn’t just turn heads, it blew minds, when it launched three years ago. And now it comes in an affordable, aluminum-frame option.

Last updated 6 September Not listed for 1,667 days

Slash 9.9 XO1

$8049.99 msrp.

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