Trek has updated the Slash long-travel bike its factory enduro race team competes on, giving it more rear-wheel travel, mixed wheel sizes as standard, and a new high-pivot and chain idler suspension design.
The brand’s aim was to arm the Slash with more capability for the wildest trails, so enduro racers, bike-park rippers and anyone wanting to push their limits can hit the trails hard and ride back to the top.
There are seven new models being released: two aluminium bikes and five carbon-framed offerings. Plus, there are aluminium and carbon framesets available.
Prices range from £4,250/$4,399.99/€4,499/AU$6,999.99 for the Slash 8 base model to £11,750/$11,499.99/€12,499/AU$19,499.99 for the top-spec carbon option.
High-pivot calling
Trek’s latest Slash has a new high-pivot suspension layout designed to better absorb bumps. Sam Needham
Trek is no stranger to a high-pivot bike. The Session downhill bike has been using this design since 2021. Trek says it has been playing around with high-pivot designs for years, and went through multiple iterations to learn how best to implement its design on the Slash.
The new high-pivot Slash dishes out 170mm of rear-wheel travel, delivering a rearward axle path, enabling the back wheel to move with the bump force path.
The 2024 Trek Slash gets increased rear-wheel travel for downhill performance. Trek Bikes
The maximum rear-centre growth is approximately 18mm rearward at 135mm travel, before the axle path arcs forwards again for the last 40mm of travel. This path is also intended to not get hung up on square-edge hits to better maintain momentum on the trail.
At 30 per cent sag, the chainstays are approximately 11mm longer than the static geometry chart states.
The idler reduces pedal kickback by eliminating chain growth as the suspension compresses. This is particularly noticeable on a high-pivot suspension system.
Its position has been calculated carefully to keep as much pedal efficiency as possible, enabling Trek to fine-tune the anti-squat, which it claims stays above 100 per cent through its whole travel.
The large 19T upper idler helps minimise drivetrain friction and is placed to keep anti-squat around 100 per cent through the whole travel. Sam Needham
As with some other bikes, the leverage rate can also be changed with a flip chip on the lower shock mount. This increases it from 20 per cent to 25 per cent, making it harder to compress the suspension in the later setting, meaning the bike is suitable for both a coil and air shock.
The oversized 19T upper idler is also said to reduce drivetrain friction. The lower idler, built in collaboration with MRP, mitigates chain growth below the chainstay.
This stops the suspension causing the chain to pull on the derailleur’s cage to improve suspension sensitivity. It is also intended to improve drivetrain smoothness.
The MRP lower idler helps keep the lower chain length consistent to reduce pull on the rear derailleur. Sam Needham
If you need to replace the chain, the new design uses one standard 126-link chain in all sizes except the extra-large, which uses a 128-link chain.
While the suspension layout is new, Trek has retained its ABP (Active Braking Pivot) at the chainstay/seatstay junction, which rotates concentrically around the rear axle. This keeps the Slash as a single-pivot, linkage-driven shock platform.
New look, new shape
Trek has also updated the geometry. Sam Needham
It’s not just the suspension that has been overhauled, with the frame’s geometry seeing updates to make it a burlier bike.
There are five frame sizes to choose from – small, medium, medium/large, large and extra-large. The small frame rolls on 27.5in wheels front and back, while the other four sizes use a mullet setup with 29in front and 27.5in rear wheels.
The M to XL bikes can fit a 29in rear wheel, but you need to purchase a different lower shock mount, which lowers the bottom bracket to make it compatible with the bigger wheel.
The standout differences are the head tube angle is now a slacker 63.3 degrees as stock (mixed wheels, 170mm fork) for the M-XL, and 63.5 degrees on the S.
Trek has also introduced ∓1-degree headset cups that can be fitted to the head tube. These are available aftermarket, and they enable you to tailor the front-end geometry to suit your preference.
Trek has made the Slash slacker, but not longer. Sam Needham
There is also a steeper effective seat tube, of around 77 degrees, to help set riders centrally when climbing. The straighter seat tube means the size-S bike can fit a 170mm dropper post, while M bikes and above can fit a 200mm or longer dropper, to really get the saddle out of the way in the descents.
To accommodate longer droppers, the seat tubes are shorter, starting at 390mm on the size S and topping out at 470mm on the XL.
The reach numbers are as you would expect from a bike with these attributes. They are 430mm (S), 448mm (M), 468mm (M/L), 488mm (L) and 513mm (XL).
It’s interesting to see Trek has made the Slash slacker, but not longer. These values are how the bike is sold. If you fit a 29in wheel, or change the headset cups, the geometry will change too.
Trek has built in proportional chainstay lengths as frame sizes increase. These range from 429mm (S and M) to 434mm (M/L and L) and 439mm (XL). While these seem very short, remember the rear-centre length will grow 11mm at sag, but these should still give the bike agile handling.
The devil’s in the details
The Slash’s new chainstay protector is designed to reduce lateral and vertical chain movement to minimise noise. Sam Needham
While there is plenty new with the latest Slash, Trek has kept its OCLV Mountain (Optimum Compaction Low Void) carbon fibre. This construction is intended to increase the carbon’s strength and impact resistance.
However, Trek has added Integrated Carbon Armour. This is an additional layer of film that lies below the paintwork to give extra protection to the carbon.
The aluminium models get Trek’s Alpha Platinum Aluminum, which uses the brand’s highest-grade aluminium and construction process.
There are also new replaceable fenders under the down tube to fend off rock strikes and impacts. One sits at the bottom bracket, and the other offers protection against pickup truck tailgates.
A new rear fender has been integrated into the bike and styled to match modern front fenders. This only fits the 27.5in rear wheel, and will need to be removed for clearance to install a 29in wheel.
Trek has revised its internal frame storage with a larger opening and easier access. Sam Needham
To help keep the bike silent, Trek has designed a new chainstay protector. The shape is claimed to prevent chain whip, and minimise both vertical and lateral chain movement, leading to less noise.
To the pleasure of many, Trek hasn’t used internal headset routing. However, there are new internal cable guides, Trek calls Chunnels, that enable better use of the Slash’s internal frame storage.
Furthermore, it gets a new hatch with a bigger opening to help stash larger items. There is also a new, more reachable lever, which should make opening the compartment easier. Trek says it has used recycled plastic for its internal frame storage.
The bike uses common standards, including Boost 12x148mm rear hub spacing. There’s a threaded bottom bracket shell and 55mm Boost chainline. The rear brake uses a minimum 200mm flatmount, and can accept a 220mm maximum rotor size.
Trek Slash prices and specifications
There are seven bike specifications to choose from. Two bikes sport the aluminium frame and five use the carbon version.
Trek Slash 9.9 XX AXS T-Type
Trek Slash 9.9 XX Eagle AXS T-Type (Flight Attendant not shown). Trek Bikes
- Frame: OCLV Mountain Carbon, 170mm travel
- Fork: RockShox ZEB Ultimate Flight Attendant, 170mm travel
- Shock: RockShox Vivid Ultimate
- Drivetrain: SRAM XX Eagle AXS, T-Type
- Brakes: SRAM Code Ultimate
- Wheels: Bontrager Line Pro 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager RSL Integrated handlebar/stem, 820mm (w), 35mm (l)
- Saddle/seatpost: Bontrager Arvada/RockShox Reverb AXS
- Price: £11,750/$11,499.99/€12,499/AU$19,499.99
Trek Slash 9.9 XTR
Trek Slash 9.9 XTR. Trek Bikes
- Frame: OCLV Mountain Carbon, 170mm travel
- Fork: RockShox ZEB Ultimate, 170mm travel
- Shock: RockShox Vivid Ultimate
- Drivetrain: Shimano XTR M9100
- Brakes: Shimano XTR M9120
- Wheels: Bontrager Line Pro 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager RSL Integrated handlebar/stem, 820mm (w), 35mm (l)
- Saddle/seatpost: Bontrager Arvada/Bontrager Line Elite Dropper
- Price: £10,800/$9,599.99/€11,499/AU$15,499.99
Trek Slash 9.9 X0 AXS T-Type
Trek Slash 9.9 XO Eagle AXS T-Type. Trek Bikes
- Frame: OCLV Mountain Carbon, 170mm travel
- Fork: RockShox ZEB Ultimate, 170mm travel
- Shock: RockShox Vivid Ultimate
- Drivetrain: SRAM X0 Eagle AXS T-Typre
- Brakes: SRAM Code Silver
- Wheels: Bontrager Line Pro 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager RSL Integrated handlebar/stem, 820mm (w), 35mm (l)
- Saddle/seatpost: Bontrager Arvada/RockShox Reverb AXS
- Price: £9,400/$9,399.99/€9,999/AU$17,499.99
Trek Slash 9.8 GX ASX T-Type
Trek Slash 9.8 GX Eagle AXS T-Type. Trek Bikes
- Frame: OCLV Mountain Carbon, 170mm travel
- Fork: RockShox ZEB Select+, 170mm travel
- Shock: RockShox Vivid Select+
- Drivetrain: SRAM GX Eagle AXS T-Type
- Brakes: SRAM Code Bronze
- Wheels: Bontrager Line Elite 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager Line Pro carbon, 820mm, Bontrager Line Pro, 35mm
- Saddle/seatpost: Bontrager Arvada/Bontrager Line Elite
- Price: £7,500/$7,999.99/€7,999/AU$10,499.99
Trek Slash 9.8 XT
Trek Slash 9.8 XT. Trek Bikes
- Frame: OCLV Mountain Carbon, 170mm travel
- Fork: RockShox ZEB Select+, 170mm travel
- Shock: RockShox Vivid Select+
- Drivetrain: Shimano Deore XT M8100
- Brakes: Shimano Deore XT M8120
- Wheels: Bontrager Line Elite 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager Line Pro carbon, 820mm, Bontrager Line Pro, 35mm
- Saddle/seatpost: Bontrager Arvada/Bontrager Line Elite
- Price: £7,425/$7,399.99/€ 7,899/AU$11,599.99
Trek Slash 9 GX AXS T-Type
Trek Slash 9 GX Eagle AXS T-Type. Trek Bikes
- Frame: Alpha Platinum Aluminum, 170mm travel
- Fork: RockShox ZEB Select+, 170mm travel
- Shock: RockShox Vivid Select+
- Drivetrain: SRAM GX Eagle AXS T-Type
- Brakes: SRAM Code Bronze
- Wheels: Bontrager Line Comp 30
- Tyres: Bontrager SE6 Team Issue 29×2.5in (f), Bontrager SE5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager Line alloy, 820mm, Bontrager Elite, 35mm
- Saddle/seatpost: Bontrager Verse P3/Bontrager Line
- Price: £5,175/$5,799.99/€5,499
Trek Slash 8 XT
Trek Slash 8 XT. Trek Bikes
- Frame: Alpha Platinum Aluminum, 170mm travel
- Fork: Fox Rhythm 36, 170mm travel
- Shock: Fox Float X Performance
- Drivetrain: Shimano Deore XT M8100
- Brakes: Shimano M6100/M6120
- Wheels: Bontrager Line Comp 30
- Tyres: Bontrager XR5 Team Issue 29×2.5in (f), Bontrager XR5 Team Issue 27.5×2.5in (r)
- Bar/stem: Bontrager Line alloy, 820mm/Bontrager Elite, 35mm
- Saddle/seatpost: Bontrager Verse P3/Bontrager Line
- Price: £4,250/$4,399.99/€4,499/AU$6,999.99
Trek Slash 9.9 X0 Eagle AXS T-Type initial ride impressions
BikeRadar technical writer Luke Marshall was fortunate enough to spend an afternoon on the Trek Slash 9.9 X0 Eagle AXS T-Type in Whistler, Canada before its launch. This consisted of a pedal loop through the area’s natural tech, and a couple of Creekside bike-park laps on black and blue trails.
Luke also had the bike for a day back on his local testing trails around the Forest of Dean in the south west of England. Expect a full review coming soon, but these are his initial thoughts.
This is without doubt the most efficient high-pivot idler bike I’ve pedalled. Trek has managed to keep additional drivetrain friction to a minimum, and there’s no real discernable difference between the Slash’s pedal efficiency and a traditional drivetrain setup. Trek has shown what’s possible here and it’s impressive.
This means the bike’s climbing ability is judged on its suspension kinematics, geometry, weight and tyres. Its 15.92kg (size M/L) is competitive and the Trek SE6 and SE5 Team Issue tyres roll well, which helps it climb easily.
The 77-degree effective seat tube angle kept me balanced nicely over the centre of the bike, and even though there’s a slack head tube angle, the front end doesn’t wander.
Pedalling over rough terrain with the shock open gives a smooth ride feel and there’s plenty of traction. The suspension is pretty active without being overly wallowy.
On smoother trails, it’s best to lock out the shock for maximum efficiency. However, I could ride up most gradients with the shock open without much fuss. Its climbing manner is impressive for its nature and on-paper stats.
On the descents, I found the rear suspension didn’t provide a super-smooth feel, as you might expect from the high pivot. However, the suspension is still supple, sensitive and flutters across the bumps.
While the travel is plush, there’s good support in the mid-stroke that enables you to pop and pump down the trail, and gives the bike a lively and light ride character, while still remaining stable and composed when the trails get rough.
Trek seems to have found a good middle ground between keeping the bike engaging and maintaining its bump-swallowing abilities.
I was pleasantly surprised by how light-footed the Slash feels while still hunting out traction. It’s easy to ride and drops into and out of turns confidently without needing tons of effort to muscle it around.
Also, considering its high-pivot design, the suspension performance is impressive under braking. That helps give the bike traction on steep trails, which enables you to build confidence and attack when trails and the gradient are high.
The bike is also near-silent, which is brilliant.
However, the most noticeable issue so far is the Bontrager tyres, which can’t match the best mountain bike tyres for grip and confidence.
That said, my initial impressions of the Slash have been very positive, and I look forward to spending more time on the bike. Keep your eyes peeled for a full review soon.
