Trek Fuel EXe Review

Trek Fuel EXe

The lightweight e-mountain bike genre has been gaining traction rapidly in the past six months. It’s a category that Specialized pioneered back in 2020 with the Levo SL and their SL1.1 motor. However, while the SL whet the appetite of many and teased at the possibility of a sub 19kg motorised bike that could do it all, the category never really took off. That was until this year, when firstly Fazua launched their Ride 60 platform (60nm motor and 430wh battery) which was quickly adopted by Pivot and Transition, and then came the launch of  the new Trek Fuel EXe with a brand-new motor and battery system from TQ.

Electric test bikes have been notoriously hard to get hold of the past couple of years, so we were absolutely fizzing when they got in touch to say they were shipping us a new Trek Fuel EXe to review. The concept of a lighter weight, better handling e-bike had enthralled us since we first tested the Levo SL, and while the SL was a great bike, ultimately the motor’s lack of power (35nm) left it trapped in limbo between analogue and electric. Trek transcended this by teaming up with German tech company TQ to develop a totally new system which, after four years in the making, launched on the Fuel EXe with some impressive numbers—a 50nm motor with a 360wh battery and a complete weight (motor and battery) of 3.9kg.

TQ are no strangers to the world of electric motors, having debuted their insanely powerful 120nm (HPR120) drive unit in the eMTB segment almost ten years ago. The 120 held the prize as the most powerful motor on the market but wasn’t widely used outside of Europe. The new TQ HPR50 motor uses the same Harmonic Pin Ring (HPR) technology to provide the motor’s power.
If you can imagine two cogs, one smaller than the other which rotates inside the bigger cog, that is the essence of how the HPR drive works. No belts, chains or gears to make noise or wear out. Just a sleek, simple mechanism that weighs in at a meagre 1.85kg for its 50nm output. To put those numbers into perspective, the two industry leading full-size motors—the Bosch CX Performance Line and the Shimano EP8 weigh 2.9kg and 2.6kg respectively and both produce 85nm of torque.

As the name suggests, Trek have decided to use their trail bike, the Fuel EX, as the basis for their new lightweight e-MTB. The EXe sports 150mm front and 140mm rear suspension on a 29” platform and carried over the numbers from the EX’s recent geometry update—Our medium test bike in the Low setting had a 65-degree head angle, 455mm reach, sporty 440mm chainstays and 77-degree effective seat tube. These all sit in the sweet spot for the mid-travel trail-focused bike. The exciting number for me was the shortish chainstays which hintedat an agile ride, which I guess was possible due to the small size of the TQ motor.

I’m going to start this section on the bike’s spec with a caveat—When you look at the images of the bike I tested and then jump over to the Trek New Zealand’s webpage you will be rightly confused! This is because Trek decided to send all the world’s media their opulent 9.9 XX1 AXS model in bright yellow to test. This is pretty standard practice for reviews, by supplying the ultra-fussy, gear-snobby paparazzi the best of the best, it negates some of our ability to whinge and moan about the bikes spec, which in turn hopefully focuses our reviews on the bike itself. However, the conundrum I faced was that the 9.9 was not even ranged in New Zealand. In fact, it was a long way above the top NZ bike the 9.8XT. Therefore, I took this as poetic license to get creative with the EXe (ignore certain components and swap out others) and see if I could relate my review a bit more to the NZ market and the models we have here.

Luckily all the bikes in the Fuel EXe range are based around the same core components—Trek’s OCLV Mountain Carbon 29” frame and the brand new TQ HPR50 motor and 360Wh battery—so I’ve focused my review on these. For the tech geeks out there, my 9.9 was fully kitted with AXS XX1 drivetrain, AXS dropper post, Bontrager’s Line Pro 30 wheelset and RSL integrated handlebar and stem. A Rockshox Lyrik with new Charger 3 damper and Super Deluxe Ultimate shock provided the support and the whole package weighed in at 18.5kg.

The TQ motor surprised me with its intuitive feel and lack of noise. It was amazing and virtually silent and I instantly realised how much noise effects the quality of your ride on an e-bike.

For my first ride, I just set up my suspension and rode it as it came out of the box. I went for a quick 40 minute pedal and was blown away, underwhelmed, and confused all at the same time.

Blown away:  The TQ motor surprised me with its intuitive feel and lack of noise. It was amazing and virtually silent and I instantly realised how much noise effects the quality of your ride on an e-bike. During the EXe’s online launch, Trek and TQ spent a lot of time emphasising how quiet the HPR50 was, which at the time I’d dismissed as marketing hyperbole, but now I understood what a difference it makes. I was also very impressed by the bike’s responsiveness and handing.

Underwhelmed: As I hit the first climb, I was quite taken back as to what 50nm of torque can and can’t do—I had to change gear and pedal! However, as a regular e-biker I was comparing the EXe to my full size eMTB which boasts 108nm, so this wasn’t really apples with apples. Plus, the more time I spent onboard the Trek the more I realised that this was a mindset problem not a hardware issue. 

Confused: The front end of the bike felt weird, and my wrists hurt after that first ride. The first solution here was to remove the Bontrager carbon RSL one piece bar and stem—which I’m sure goes great on an XC race bike but felt incredibly stiff and ridiculously wide at 820mm for a trail bike—and replace it with my go-to bar and stem from my own bike. This helped, and after a bit of fiddling with the Lyrik’s set up (another token and less air) I felt a lot more comfortable.

A lot more rides ensued. This bike was highly addictive, and my mindset had shifted from riding an e-bike to just riding this thing like a normal bike. The harder I rode the Fuel EXe the more it responded both motor-wise and handing-wise. I quickly learned that the TQ motor likes a high cadence and, if you can hold that by staying in the right gear, the motor is deceptively powerful on all but the steepest climbs. Even then it was just a matter of downshifting to the granny gear and spinning the pedals as you would on a regular bike. Climbing wasn’t overly taxing—the motor assistance kept it easy enough—it just took more time and a bit more skill to get up steep hills, and the rewards came on the descents.

The Fuel’s geometry and very supportive suspension platform made it a rocket ship to ride downhill or on undulating terrain (motor assistance turns everything into a descent). It was also scarily agile and manoeuvrable for an 18.5kg eMTB, which led to me pushing a lot harder than I normally would on a heavy e-bike. However, it was when I pushed a bit harder that the niggly front end issue started to appear again and on a few occasions I found myself washing the front out all too easily. The standard riding position felt too aggressively XC. I wanted to add a few spacers under the stem, but this wasn’t an option because I was already at max height. 

This bike was highly addictive, and my mindset had shifted from riding an e-bike to just riding this thing like a normal bike. The harder I rode the Fuel EXe the more it responded both motor-wise and handing-wise.

After a quick sleuth through the media kit, I discovered that Trek was open to the idea of the Fuel EXe being run as a mullet or upgrading the fork to 160mm. And it just so happened that I had a 160mm fork with the right offset on my trail bike. So, in the interests of testing, I swapped the 150mm Lyrik with my 160mm fork and went for a ride.

The difference was instant, the slacker ride position felt a lot more me and when I pushed hard on steeper trails the front held better and I lost my fear of washing out. A new problem arose—I was now completely addicted and finding it hard to ride anything else.

I was returning from rides sweating and tired with the feeling of having been for relatively high-intensity ride. Yes, they were long rides (I had a motor) but with the extra effort required to get up hills I felt more like I was riding my trail bike on steroids rather than taking my moto-style eMTB out for a burn. My mindset had shifted because the EXe was performing like the perfect hybrid. 

The hardest trait of the EXe to get your head around is the battery usage and the range-anxiety that comes when only sporting a 360wh battery. First up it’s worth noting that via the Trek Central phone app you can customise each of the three modes on your bike. I left the Turbo mode as exactly that—100 per cent power and assist—but aimed to only use it when really needed. Then I adjusted the Trail mode to give me 75 per cent power and assist and left the Eco one at about 30-35 per cent. My goal here was to just ride in the trail setting as much as possible and see how I went. The control panel built into the top tube also gives you an estimated range, which is another useful tool. 

From my experiences over the test window riding predominantly in Mid mode (only utilising High for steep climbs), I’d say the EXe is good for 30-35kms of hard trail riding with moderate climbing. This can be eked out to over 40km with a bit more cautious battery management. So, my advice (and the way I think Trek has designed it) is that the range extender battery is a must-have for anyone looking to push themselves on long, full day rides. It is an expensive add on, but I think the benefits outweigh the initial costs. The flipside is that, even without any electrical assistance (flat battery), the Fuel is very rideable, and there is very little drag in the TQ system, so a pedal home is not a big chore. Plus, the beauty of a small battery is that it charges very quickly, so I’d make sure you always have your charger in the truck with you and take any chance you get to top up.

I’m sure you’ve already guessed that I really fell for the Fuel EXe and for me it has blown open the electric bike world by re-defining the lightweight category. The 50nm motor provided ample power and the light, nimble chassis handles remarkably well. This is the sort of bike that I’ve been waiting for; as a regular rider of both analogue and eMTBs, I’ve been chasing the dream of an electric powered (for time saving) bike that handles as close to my analogue bike as possible (for ultimate ride enjoyment), and I feel like the EXe is the closest to that hallowed hybrid bike. Add in the experience of riding an almost silent motor and maybe this is the dream—well my dream, but is it for everyone?

What type of rider will the EXe suit? I feel that it firmly suits any skilled or experienced rider looking to electrify their riding experience. I’ve chosen the words skilled and experienced because the EXe needs a lot more rider input than full powered eMTBs. By input I mean being in the right gear at all times, holding a fast cadence and precise bike handling. These factors are natural and necessary skills for most analogue trail riders, but they can often be ignored and forgotten on long travel, high torque e-bikes where the motor’s power will drag you up hills in any gear and any cadence and the plush suspension lets you monster-truck down any line.  

If you’re an e-curious analogue rider wondering what all the fuss is about, then this is definitely worth a test ride. If you’re already jumped into the electric world but are missing that nimble, agile handling of your old analogue and have reasonable residual fitness, then maybe it’s time to downsize.

Of the three models coming to New Zealand, my advice is to buy the best you can afford but leave a little in reserve to add on the range-extender battery as I feel this is essential to alleviate any range anxiety. If you’re a more aggressive rider or are finding the riding position too forward orientated, then I’d also recommend getting your local shop to increase your fork travel by 10mm for the ultimate trail bike feel.

The stealthy looking EXe and the TQ motor system have set the bar very high and reinvigorated the lightweight eMTB category. I’m sure there is a lot more coming in this space, perhaps very soon, but the EXe and the eerily silent TQ HPR50 will be very hard to beat.  

Check out the full EXe range available now in NZ over at the Trek website