All Arround MTB

Things have been a little quiet from French suspension wizards BOS over the past year or so, but that looks set to change, thanks in part to this beast of a fork, which was on display at this autumn’s huge Eurobike show (see p61). The Obsys is BOS’s new airsprung downhill fork. It’s inverted, uses 42mm-diameter stanchions to ensure torsional stiffness and steering accuracy, and delivers a massive 220mm of travel – or 200mm if you want to use it with 29in wheels, in which case you may want BOS’s adjustable-offset steerer (59 or 53mm vs 56mm). Damping comes courtesy of their revised sealed-cartridge ‘FCV’ unit, which allows for rebound and low-speed compression to be adjusted externally. The twin valve heads sticking out of the top of the left-hand leg are used to adjust preload and air pressure. At a claimed 3,100g it’s certainly not light, and we’ve got a feeling that it won’t be cheap either. BOS know a thing or two about suspension though, so this should be one hell of a fo...

The Deville has very limited chassis options and isn’t as stiff as chunkier forks, but BOS’s latest FCV damper offers incredible grip and support if you’re patient enough to tune it right. With 34mm legs and no 29er or Boost options, this fork is looking dated. Despite cutouts in the skinny brace and obvious twist and tuck if you’re using a big rotor and bar, it’s still over 2kg too. The stepped 15mm axle system is beautifully machined to underline the premium quality and cost. There’s a 20mm axle kit too, but tyre/fender space is limited. The FCV damper has come from BOS’s rally experience via the Idylle DH fork. Get the balance of low and high-speed compression damping right and it opens up a fantastic mix of support for pushing crazy-hard through corners but ultra-sensitive traction to keep you railing no matter how random the rocks and roots get. It’s enough to make even an average tyre feel amazing and lets you stay head up, heels down and bar slammed even when you can feel t...

THE NEW DEVILLE RaRe FCV enduro fork from French company BOS contains their latest tech innovation, the Frequency Control Valve. It’s basically an inertia valve inside their hydraulic cartridge and acts as a second damper, which is claimed to offer hugely increased comfort and control on rocky terrain, while also improving small-bump absorption.

BOS has a well-earned reputation for superb suspension and the heritage is clear in this light yet superbly performing fork.