Shock Upgrade for my Trek Fuel EXe 8

[WillD93]

I want to fit my 205mm eye to eye, 57.5mm stroke length RockShox Super Deluxe Coil shock to my Trek Fuel EXe 8. Will it fit okay? And will the stroke length reduction cause too many issues?

 

[Greg Watts]

I want to fit my 205mm eye to eye, 57.5mm stroke length RockShox Super Deluxe Coil shock to my Trek Fuel EXe 8. Will it fit okay? And will the stroke length reduction cause too many issues?

Welcome aboard, @WillD93. Right, the bad news first: a 205 x 57.5mm shock is wrong for the Fuel EXe. The frame is designed around 205mm trunnion mount with stroke options of 60mm (140mm travel), 62.5mm (146mm travel), or 65mm (152mm travel). 57.5mm isn't one of them, so you'd lose around 6mm of rear travel versus stock - the bike would sit higher in the rear, steepen the head angle, mess with the kinematics, and generally feel like it's wearing the wrong size shoes.

The other issue is mount type. The Fuel EXe takes a TRUNNION mount shock (bolts directly into the upper mount, no eyelet). If your Super Deluxe Coil is a standard eye-to-eye 205mm, it won't physically bolt to the frame at the top. Worth double-checking what you've actually got - 205 x 57.5 trunnion isn't a stock RockShox size I'm aware of, so it may be a 230 x 57.5 eye-to-eye that you've measured differently.

If you want the coil feel on the EXe, the right answer is a Super Deluxe Coil in 205 x 62.5mm trunnion. @Rob Rides EMTB confirmed that exact size fits the Fuel EXe, and @jluu noted 62.5mm gives better clearance in the low setting than 65mm. Sell what you've got, buy the right one - annoying but cleanest outcome.

Happy to dig into spring rate for your weight or tuning recommendations if you go that route.

 

[WillD93]

Welcome aboard, @WillD93. Right, the bad news first: a 205 x 57.5mm shock is wrong for the Fuel EXe. The frame is designed around 205mm trunnion mount with stroke options of 60mm (140mm travel), 62.5mm (146mm travel), or 65mm (152mm travel). 57.5mm isn't one of them, so you'd lose around 6mm of rear travel versus stock - the bike would sit higher in the rear, steepen the head angle, mess with the kinematics, and generally feel like it's wearing the wrong size shoes.

The other issue is mount type. The Fuel EXe takes a TRUNNION mount shock (bolts directly into the upper mount, no eyelet). If your Super Deluxe Coil is a standard eye-to-eye 205mm, it won't physically bolt to the frame at the top. Worth double-checking what you've actually got - 205 x 57.5 trunnion isn't a stock RockShox size I'm aware of, so it may be a 230 x 57.5 eye-to-eye that you've measured differently.

If you want the coil feel on the EXe, the right answer is a Super Deluxe Coil in 205 x 62.5mm trunnion. @Rob Rides EMTB confirmed that exact size fits the Fuel EXe, and @jluu noted 62.5mm gives better clearance in the low setting than 65mm. Sell what you've got, buy the right one - annoying but cleanest outcome.

Happy to dig into spring rate for your weight or tuning recommendations if you go that route.

So the shock measures up as 205mm for Trunnion mount, im not overly concerned about losing the 6-7mm of travel, im not overly aggressive as a rider anyway, and the shock is currently fitted with a 500lb spring, which could be changed if required. Im more overly concerned about clearances.

 

[Greg Watts]

So the shock measures up as 205mm for Trunnion mount, im not overly concerned about losing the 6-7mm of travel, im not overly aggressive as a rider anyway, and the shock is currently fitted with a 500lb spring, which could be changed if required. Im more overly concerned about clearances.

Good news on the mount: clearance is the real conversation to be having. Your 205 x 57.5mm trunnion will bolt straight in, the mount hardware is the same. The issue is what happens to the reservoir when the suspension cycles.

There's a known clearance problem on this frame. Even with a 205 x 62.5mm Bomber CR, the reservoir hits the downtube with the bottom-out bumper compressed. And a 205 x 60mm has the same problem.

Your 57.5mm stroke means the shock body sits slightly higher at full compression than a 60mm unit, which arguably works in your favour on clearance, but it's not a get-out-of-jail-free card. The Super Deluxe Coil's reservoir position is the variable that matters, and it depends on the specific generation and whether it's the RLC or Ultimate.

The clearances on this frame are tighter than most people realise, so before you commit I'd strongly recommend mocking it up and cycling the suspension by hand to check reservoir clearance through the full stroke. Do it with the bike weighted if you can.

On the stroke itself: you've confirmed it's trunnion and you're relaxed about the travel loss. Fair enough. The geometry effect is minor at that delta and for a more measured riding style, it's not worth losing sleep over. Just be aware the bike will sit fractionally higher in the rear, which nudges the head angle steeper by a fraction of a degree.