Photos by Dusten Ryen
Video by Brian Niles/Treeline Cinematics

After the Trek Rail took the top spot in our 2020 eMTB shootout, we had high expectations of the refreshed 2021Trek Rail 9.9. Much of the bike is familiar, which isn’t a bad thing since the 2020 model blew us away. That said, things move fast in the eMTB world so will the 2021 model refresh have what it takes to hold its own against a stacked field of completely re-designed competitors? We threw everything the Utah desert had at the Rail to see if it could defend the top spot.

The Trek Rail 9.9 is built around a full OCLV carbon frame, which is wrapped around the Bosch Performance Line CX motor and battery system. OCLV carbon is a proprietary process that Trek has developed to minimize voids within their layup. Protecting the carbon are molded elastomeric armor bits on both the down tube and chainstays. We would like to see a slightly more durable clear coat on the paint however, so be prepared to buy a clear frame protectant sticker wrap to keep this beautifully cherry and raw carbon bike looking good.

Geometry is unchanged from last year, which is perfect since the existing bike was right in the Goldilox zone. A high/low adjustable chip is integrated into the rear linkage to allow riders to lower the bottom bracket and slack out the head tube angle. We rode the bike mostly in the low setting, which gives a 64.5-degree head tube, 75-degree seat tube, 465mm reach, 448mm chainstay and a 630mm stack height. The Trek Rail is more than the sum of the measurements though, and for that reason we love this bike on a wide variety of terrain.

Something we have to mention as it has plagued multiple Trek test bikes we’ve ridden is hardware coming loose. Once again we had some loosening from the rear axle, almost daily until we put some thread locker on, and other hardware in the Mino-Link and rockers have come loose. We hope that Trek can start using some stronger thread locker because we’ve definitely had a ride ruined from parts falling out.

2021 eMTB Shootout: Trek Rail 9.9 Review

Bosch’s Performance Line CX motor and battery system with Kiox display is a solid way to go, and while one tester had an issue knocking the screen off with his knees, we’ve never seen anyone else have this issue. The motor puts out 85nm of torque in both eMTB and Turbo mode, which is an increase from 75nm last year. The increased torque gives the rider instant power in all scenarios and cadence speeds. Coupled with a 625wh battery, this motor is leading the competition in both sustainted peak power and longevity. We ran several other batteries dry while the Bosch still had more than 30% on the meter. This drivetrain absolutely has its distinct advantages.

With the $10,499 price tag, you get an impressive component spec, and rightfully so. The build includes a RockShox ZEB Ultimate 160mm fork and a Super Deluxe Ultimate RT3 rear shock sporting 150mm of travel. While we think the Fox 38 may have the slight edge in performance, the RockShox Ultimate stuff is very comparable, especially with all the time and effort Trek and RockShox put in to fine tune their ThruShaft technology. Drivetrain duties are handled by 12-speed SRAM X01 Eagle with SRAM Code RSCs brakes and a 200mm front rotor and 180mm rear. The cockpit, dropper and wheels are all Bontrager. The 780mm wide bars are OCLV carbon with 35mm rise and feel as good as any non-OEM part. The wheels are a carbon masterpiece, blending compliance and strength and we’re huge fans of Bontrager’s new and improved wheels.

2021 eMTB Shootout: Trek Rail 9.9 Geo
2021 eMTB Shootout: Trek Rail 9.9 Review

To describe the climbing performance of the Trek Rail 9.9, simply insert any positive descriptor you can think of and press go. Thanks to the torque of the Bosch system, geometry and Trek’s supple suspension design, we were all reaching for the Rail on challenging climbs. The motor seems to churn out endless power at even the lowest cadence, but not enough to constantly raise the front tire or break traction. The long wheelbase is balanced out by the chainstay length and 64.5-degree head tube keep it from being too cumbersome on the super tight stuff.

Seating position feels neutral and standing efforts have enough room, although we wouldn’t mind a couple more milimeters of reach to get us closer to 475mm. But if you’re looking to impress your friends or win a free burrito from the crew, simply put it in Turbo and your only limits are skill and gravity. After several battery draining days on the rest of the bikes, the Trek Rail still managed to have a battery bar remaining. The Kiox display screen is the best in the Bosch lineup, and is tucked neatly behind the stem on the top tube.

The charging port is well covered with a flip down door that is paint matched to the body and we never had any issues with the battery or cable rattle we experienced with several other eMTBs this year. A big benefit of the Rail is an integrated aluminum skid plate covering the bottom bracket and motor. We are finding that skid plates are an essential item with low hanging motors, and the Rail’s is definitely a very stout version and resisted breaking, unlike several other bikes we tested. The motor casing does have a few deep gouges in it from sharp rock impacts, but it’s still working just fine.

2021 eMTB Shootout: Trek Rail 9.9 Review

The Trek Rail 9.9’s total package is pretty dialed. The new rear shock tune with RT3 technology is just about perfect, with enough support in the mid travel to always allow for a big drop or jump, while still maintaining ground tracing sensitivity off the top. We’ve had a bit of trouble with RockShox rear shocks spitting oil after some time and it seems that this one is keeping oil inside rather than making our bike dirty, which we appreciate. Overall we really liked how the shock blended sensitivity with the ability to keep up with big, harsh hits at speed.

Many of our testers noticed the Trek Rail kept up with many bikes in the Enduro category of our eMTB Shootout. It’s a bike that really likes going fast and the Zeb up front makes a huge difference in confidence. While we did knock the travel ring off the rear shock several times, none of us could tell we were bottoming as the ramp up is both supportive and progressive. The stiff frame and fork allow for laser-like accuracy in line choice and the Bontrager wheels are flexible enough to hold side hill options with ease.

Off big, slow speed drops, the Trek Rail needs a little extra effort to get the long wheelbase balanced. The front end feels a tad heavy when trying to keep it up off those slow drops out of corners. The low bottom bracket and taller stack give the feeling of riding in the bike rather than on it, and provide the confidence to tackle whatever. We rarely find bikes that flick through switchbacks just as well as they hold tight inside turns, but the Rail does exactly that. Whether you like to scandi turn into big berms or just get off the brakes and rail the corner, the snappy rear end, supple suspension and capable geometry make it happen.

We cannot end without discussing the dark matte grey and gloss candy red carbon. It is both understated and refined at the same time. In darker light, the carbon weave pops through the paint, but in full sun, the red pops and impressed us all. This is one good looking machine, but sadly after a ride in the mud with our knee pads rubbing against the frame, some serious haze has developed. While the bike looks like a masterpiece new, and we love it, the clear coat needs to be a little more durable.

2021 eMTB Shootout: Trek Rail 9.9 Review

The Wolf’s Last Word

It was a close competition in the Trail category this year. Several bikes stood out in certain areas, but once again, not much could match the Trek Rail 9.9 on every type of terrain. The Bosch system will get you up any trail with battery life to spare, and likely let you clean sections you never thought possible. The geometry is also as close to perfect as we have found for all around riding, but we would like a couple extra millimeters on the reach. It is however, just long enough to hold any line you choose but retains the liveliness and pop of the best trail bikes. While we would like to see slightly more powerful brakes and possibly a Fox suspension package, that would not hold us back from buying the Rail as our only bike. Yeah, it is that good. Just don’t forget to Loc-Tite and check your linkage bolts.

Price: $10,499.99
Weight: 51.3 lbs
Website: Trek.com


Frame: OCLV Mountain Carbon, 150mm
Fork: RockShox ZEB Ultimate | 160mm
Shock: RockShox Super Deluxe Ultimate RT3

Motor: Bosch Performance CX | 250 W, 85 Nm
Battery: Bosch PowerTube | 625Wh
Display: Bosch Kiox with Anti-theft solution

Brakes: SRAM Code RSC | 200mm
Shifter: SRAM X01 Eagle, 12 speed
Headset: Knock Block Integrated
Handlebar: Bontrager Line Pro | 780mm, 27.5mm rise
Stem: Bontrager Line Pro | 45mm
Saddle: Bontrager Arvada
Seatpost: Bontrager Line Elite | 170mm

Wheels: Bontrager Line Elite 30
Front tire: Schwalbe Magic Mary 29 x 2.6″
Rear tire: Schwalbe Big Betty 29 x 2.6″

Cranks: E*thirteen E*spec Race carbon, 34T | 165mm
SRAM XG-1295 Eagle, 10-52, 12 speed
Derailleur: SRAM X01 Eagle
Chain: SRAM XX1 Eagle, 12 speed

2021 eMTB Shootout: Trek Rail 9.9 Review

We Dig

Best all around eMTB
Composed yet playful
Subdued color way that still impresses
Climbs anything
Battery life and torque delivery

We Don’t

Hardware/axle comes loose
Would love a 472-475mm reach
Needs more durable clear coat


Catalyst Distribution
Schwalbe Tires
Smith Optics


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