2021 Trek Slash 9.9 X01

A full carbon frame, all-new hard-charging suspension, fast-rolling carbon wheels, and SRAM's newest X01 Eagle drivetrain make this one top-of-the-line ride.

2021 Trek Slash 9.9 X01 Bike Review

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.

Geometry & Specs:

Wheel size: 29"
Rear travel: 160mm
Fork: 170mm
Wheelbase: 1263mm
Chainstay: 437mm
Reach: 486mm
Head tube angle: 64.1°

The new Slash comes in a wide range of colors and builds. ranging from 3K to 8K depending on your budget.
Bontrager Line Pro Carbon, 35mm, 27.5mm rise, 820mm width handle bars.
SRAM Code RSC 4-piston hydraulic disc brakes.
Bontrager XR Trail Pro, alloy lock-on grips come with the 9.9 build.
Bontrager BITS Integrated MTB Tool.
Securely stow a multi-tool, chain breaker, and master link in your fork’s steerer tube for quick and easy access when you need it.
RockShox ZEB Ultimate, DebonAir spring, Charger 2.1 RC2 damper, tapered steerer, 44mm offset.
Bontrager Line Elite 30, OCLV Mountain Carbon, Tubeless Ready wheels front and back.
Bontrager SE5 Team Issue, Tubeless Ready, Core Strength sidewall, aramid bead, 60 tpi, 29x2.60''
A large internal storage compartment in the down tube lets you stow tools and gear.
Bontrager BITS internal frame storage bag to keep things tidy in the frame storage.
Bontrager Arvada seat sits on top of the Bontrager Line Elite Dropper with 170mm travel.
OCLV Mountain Carbon main frame & stays with magnesium rocker link.
SRAM X01 Eagle, DUB, 30T alloy ring, Boost (55mm chainline), 175mm length.
RockShox Super Deluxe Ultimate, DebonAir spring, Thru Shaft 3-position damper, 230x62.5mm.
Ample chain stay protection comes standard with all Slash models.
SRAM X01 Eagle, 12 speed rear derailleur.
Bontrager SE4 Team Issue, Tubeless Ready, Core Strength sidewall, aramid bead, 60 tpi, 29x2.40''.
SRAM Code RSC 4-piston hydraulic disc.
Non drive side frame details.
Trek's mountain-specific carbon fiber is tougher carbon, with unique materials and layup procedures, Trek's advanced engineering, and a higher standard of testing.

What’s more, this featherweight construction also gave the bike an unmistakable agility on descents, when I was constantly urged to push and pull the Slash around like a shorter-travel machine. On descents, the bike maneuvers like something with 20 millimeters less travel, while simultaneously feeling as plush as an all-out downhill rig through meaty sections. The wheelbase is long and stable at higher speeds, while the relatively short chainstay allows for spontaneous direction changes with a minimum of fuss.

I was particularly impressed with the performance of the thru-shaft shock technology, which felt like it was keeping the suspension open to react to every rock and root I encountered. This, coupled with the 2.6-inch Bontrager tires, made for a magic carpet ride through the chunkiest of terrain.

The new Slash is an excellent option for riders who are looking for big-bike capability but are afraid that a bike with too much suspension will keep them glued to the ground. While it can devour steep, technical singletrack without breaking a sweat, what made it really special for me was how agile and lively it was through flatter tech sections.

Trek Slash 9.9 X01 - $7,999