The chassis of an all-out enduro racer married to the spec of a trail bike leaves the BMC Trailfox TF03 somewhat confused
In a world of look-a-like bikes, BMC stands out as a brand with its own identity. It has the conviction to do what it believes in, and at present that means 29in wheels on all its mountain bikes.
It hasn’t always been that way, however. Much like the rest of the industry, the development team at BMC was sceptical about the benefits of bigger wheels for trail and enduro riding, so the prototype 150mm-travel Trailfox 29 was born purely out of curiosity.
The idea was simple: build a 29er with similar geometry to the 26in Trailfox — short-ish chainstays, a low BB and a slack head angle. Easier said than done, especially achieving that 435mm chainstay length while maintaining sufficient clearance for a front mech and a 2.4in rear tyre. BMC achieved its goal by modifying the swingarm design of its APS suspension linkage, where the front mech now mounts directly to the wishbone that connects the chainstays to the seatstays.
That’s not the only change it made. To combat the increased stack height of 150mm-travel 29er forks, the Trailfox also gets a super-short head tube — 20mm shorter than the Specialized Enduro. It’s so low, in fact, that you won’t have any issue running a riser bar, or an even longer-travel fork.
Standover clearance on the Trailfox is also first rate, and the only fly in the ointment on the full aluminium TF03 frame is that the lever of the 142x12mm rear axle doesn’t clear the dropout fully, making it irksome to do up.
It’s no secret that Fox’s CTD forks have taken a bit of a kicking this year due to their lack of sensitivity and erratic damping. Well, it pains us to say that the 150mm-travel 34 Float Evolution on the Trailfox was no exception. It created CTD’s signature hand pain on anything but the smoothest trails.
On the rear, the Fox shock fared much better, but we suspect that the tune isn’t as good as it could be, because the rear suspension felt a little dead.
DT’s M1900 wheels spin with minimum resistance, but the 19mm internal rim width is a little narrow to stop the 2.4in Continental tyres from rolling around when cornering hard or running lower tyre pressures. Also there’s not much clearance between the rear tyre and the chain guide, so we could easily envisage returning from a ride without it.
Shimano SLX brakes are impressive, and while they edge ahead of the Specialized’s Formula C1s in terms of reliability, there’s not much separating them when it comes to raw stopping power.
When the Trailfox arrived we could hardly contain our excitement — it really is a stunning bike. Everything is in proportion with angles and lines that are every bit as aesthetically pleasing in the flesh, as they look on paper.
Granted, the tyre spec and gearing are nothing like as dialled as they are on the Enduro, but with a shorter head tube and slightly lower BB height the Trailfox has the edge in terms of geometry.
On smooth, flowing trails it carved perfect radius turns with ease, building speed quickly — but even here it was noticeable that the suspension, especially the fork, lacked sensitivity and grip. On steeper descents, the extra room in the cockpit and the stock 55mm stem pulled too much rider weight onto the fork, compromising both steering control and rear suspension tracking. Swapping to a 35mm Easton Havoc offered a more neutral and centred riding position that also placed much less emphasis on the fork and let the rear shock do more of the work. This one small change instantly allowed us to push the Trailfox harder on more challenging terrain — unfortunately it also fast-tracked us to the shortcomings in the Fox suspension tune mentioned earlier.
BMC is sitting on a gem. The geometry, sizing and frame finish on the Trailfox TF03 make it one of the best laid-out 29ers that we’ve thrown a leg over, but the lacklustre suspension response and some aspects of the spec instantly took the shine off the ride. It’s as if the bike has been dumbed down, or restricted, and we never came close to unlocking the Trailfox’s full potential. Yes, there were moments when we experienced its raw speed and promise, but they were too short-lived to give the Enduro Comp a real run for its money in this test.