The B'Twin Cyclo-X is built around a quality aluminium frame. It has several good design touches including high bottom bracket, short top tube and over-the-top cable routing, which mark it out as a serious cyclocross ride.
It has full Shimano 105 and a cross-specific Shimano CX50 chainset. It rolls on Mavic Aksium wheels and Hutchinson's super light Kevlar beaded Piranha2 tyres, which are exceptional for the price. The only obvious kit compromise is an budget saddle, but that's easy to change.
- BUY IF... You want a serious cyclocross ride and don't mind making a few spec changes
Initial impressions are great. The flattened top tube is comfortable to shoulder, the slender fork offers plenty of vibration damping and the tight frame is flickable and fun. The reasonably light wheels and impressive weight make it easy to spin up steep slopes. Its bi-ovalised down tube adds to the confidence-inspiring stiffness and makes you want to push that bit harder – or so we thought.
Our first speedy descent, on singletrack with an off-camber 90-degree turn midway, usually requires scrubbing speed with the front brake, then adding a grab of the rear to drift/slide into the apex. But on applying the front brake we met with a judder so violent we thought we'd forgotten to tighten the cantis. We checked. We hadn't.
We've come across this before, though not so extreme. It's caused by the centre-pull cable being anchored on a mount under the stem at the steerer. With a fork that flexes it means the distance between the cable stop and brake stretches and shortens as it moves forwards and backwards, making for a judder under braking.
We took our concerns to B'Twin but were told there are no plans to change it, which is a shame as it would be very easy to cure: either spec a mini-V-brake or use a fork-crown-mounting hanger – Tektro's costs just £7.99. In every other way the bike would be the bargain cross ride of 2013: light enough to race, tough enough to abuse and a whole lot of fun.
The brakes really let the B'Twin Cyclo-X down – if it weren't for them it might well have scored a full five stars
You could grab a bargain and fix the brake issue, but you shouldn't have to. And for a bike that's this good on paper and great for 90 percent of your ride to be fundamentally spoilt for the sake of an £8 component is a crying shame.