There is something special about a bike that can do nearly anything, and Trek has honed their new Fuel EX into a top contender in the ‘quiver-killer’ category. The recipe starts with 140/150mm travel, modern geometry and 29” wheels, but Trek decided to offer a ton of adjustability too; The frame geometry, steering angle and shock rate can all be tuned on the new Fuel EX.
The Fuel EX’s range of adjustment allows this bike to be anything from a cross-country machine to a short-travel enduro bike, and the wide range of available models offers an option for many budgets.
2023 Trek Fuel EX frame features:
All features listed below are included on both the aluminum and carbon framed Fuel EXs (except the entry-level Fuel EX 5, which uses the previous generation aluminum frame with 130mm travel and does not offer many of the features described below).
The fully redesigned Fuel EX features Trek’s ABP suspension linkage, now offering 140mm rear travel and matched to 150mm forks. Wheel size and fork travel does vary on some models; The XS frames run 27.5” wheels and a 140mm fork, and Small frames offer either 27.5” wheels (with a 140mm fork) or 29” wheels (with a 150mm fork). All larger sizes run 29” wheels front and back, but they can be converted to MX setups. However, Trek recommends a 160mm fork for mixed-wheel riders.
Trek’s Mino Link geo adjustment chip offers High or Low frame positions, and a new addition to the Fuel EX is a ‘LESS/MORE’ suspension progressivity flip-chip at the lower shock mount. This chip offers a more progressive curve to accommodate coil shocks, or simply to better suit burlier riders. Flipping this chip has no effect on frame geometry.
The new Fuel EX does not come with Trek’s Knock Block 2.0 headset. What you get instead is the option of adding angle adjust headset cups (not included) with +/- 1 degree settings.
Trek has jumped on board with down tube storage, offering a good-sized compartment with a Bontrager BITS tool roll included with all models. If you go for the high-end 9.9 bikes, you also get a Bontrager multi-tool in the steerer tube.
Key frame fitments include Boost 148 rear spacing (with Boost 110mm forks on all models), a trusty threaded 73mm bottom bracket, a beefy 34.9mm seat tube, ISCG05 chain guide tabs, and a SRAM UDH derailleur hanger.
The frames all offer guided internal cable routing, and come with down tube and chainstay protectors. Trek even added a little mudflap to keep rocks from getting between your BB shell and chainstay yoke. Maximum tire clearance for all frame and wheel sizes is 2.5” wide, and the biggest chainring you can run is 34t.
The new Fuel EX frame offers more insertion depth for dropper posts than the outgoing version. Stock post lengths are 100mm travel for XS and small frames, 150mm for the medium or M/L, 170mm on larges and 200mm on XL bikes (except the 9.9 XX1 AXS, as the longest Reverb dropper available is 170mm).
All frames can fit a water bottle, but with limits; XS frames can only run a 15oz bottle, S-M/L’s can hold up to 21oz, and large and up can fit 26oz bottles.
The higher-end Fuel EX models (9.8 XT and up) will be available as a Project One bike with custom paint options, and paint-matched replacement storage doors are available for higher-end models (lesser models get a black door).
Trek did provide weights for the Fuel EXs- To sum it up, all carbon models are under 33lbs, while the aluminum completes go up to just over 35lbs.
There is a lot of potential adjustment with the new Fuel EX frames – The Mino link can be in High or Low position, and the optional angle-adjust headsets can be in steep, neutral or slack positions. Some angles and measurements also vary according to frame sizes, so between the nine different charts Trek sent I’ll do my best to generalize things here!
Trek did provide mullet geometry, but I’ve intentionally left that out of my description below… there are enough numbers to crunch between the stock setups and headset options, so check out Trek’s website for MX geometry.
Reach numbers are generous across all sizes; the M/L I was testing is one of the longest bikes I’ve ridden at 470mm. Something new for the Fuel EX is how rear end lengths now vary according to frame size; They’re 435mm up to size Medium, 440mm for M/L or Large, 445mm for XL and 450mm for XXL.
Steering angles go from slightly steep to really slack! With the angle-adjust headset cups, the steepest angle possible is 66°, while the slackest possible is just 63.5°. With the stock neutral headset cups, the steering angle varies from 64.5 to 65°.
The Fuel EX has a steep seat tube, with different frame sizes varying from 78.9 to 76° depending on geo settings. BBs sit pretty low in the bike’s Low position, ranging from 332-335mm according to frame size. High position bumps that up to 340-343mm.
There are eight different models of the new Fuel EX (including the Fuel EX 5 using the older frame), so I’ve provided the list with pricing but you’ll have to visit Trek’s website for full build specs on each. One highlight of the specs is that the top four models all get Bontrager’s carbon wheels and RSL one-piece carbon bar/stem.
Color options for the carbon frames are Mulsanne Blue or Deep Smoke. Aluminum frames come in Matte Galactic Grey to Black Fade. There is also a Baja Yellow colorway, which is an optional upgrade on the Project One 9.8 XT model and an included option for the other 9.8 or 9.9 models.
Fuel EX 5 – $2,699.99
Fuel EX 7 – $3,699.99
Fuel EX 8 – $4,299.99
Fuel EX 9.7 – $4,699.99
Fuel EX 9.8 XT – $6,249.99 (Project One version – $6,749.99)
Fuel EX 9.8 GX AXS -$7,699.99
Fuel EX 9.9 XTR – $9,749.99
Fuel EX 9.9 XX1 AXS – $10,749.99
The Fuel EX is also available as a frameset in aluminum or carbon (pictured above). Both include a headset (compatible with Trek’s angle adjust cups) and a 2-position Fox Factory Float X rear shock. The aluminum frameset sells for $2599.99, and the carbon kit retails at $3899.99.
I’ve been riding the Fuel EX 9.9 XX1 AXS for the last few weeks, so be sure to check out my review article to see how the new Fuel EX handles itself on the trails!