Review of BOS Deville Suspension Fork


Timing is everything, and if you ride mountain bikes in the United States, your time is now. Bos Suspension, ridden to multiple world championships in downhill, cross-country, and even rally car racing, is finally available in the States. Born of competition, the Deville is a true connoisseur's component; infinitely tunable and optimized for performance in every respect.

BOS Deville Fork

Bos' reputation of tuning and testing until perfection is achieved is evident in a glance at the Bos Deville 160mm TRC 650b/27.5" Fork. From the machined tapered steer tube to the stepped lowers, every part of the system is perfect, including the axle, which threads in easily thanks to a hide-away lever and secures with one quick-release clamp. The Deville's 34mm stanchions—which Bos originated—are filled with an open bath cartridge system, allowing a much greater volume of oil to both lubricate seals and bushings and provide damping. Not only does this make for fantastically plush movement, but extends the service life of the oil—Bos calls for two oil changes per year under "extensive usage." Bos' hearalded air spring, one of the smoothest available, sits in the other leg.

Currently, many new forks are being touted as "sitting high in their travel," which is intended to reduce brake dive and wallowing in corners. For other manufacturers, why 2013 has been chosen as the year to finally address these issues is a mystery, since Bos has tuned their forks this way forever. Having a fork that behaves properly when railing corners and under hard braking is akin to bolting up lightweight race wheels in terms of its affect on performance.

The TRC (Twin Rate Curve) system is unique in that it limits the fork travel by increasing the preload in the airspring. This system effectively keeps your compression settings and rebound settings intact so, among other things, you have less bob when pedaling out of the saddle. This is a very different system from other manufacturers and lightyears ahead of the competition.

Deville Fork Suspension System

While preset hydraulic damping adjustments (CTD, RCT3) are suddenly the norm on most high-end "enduro-style" forks, Bos allows you to decide on your own settings. Separately adjustable high-speed and low-speed compression and low-speed rebound settings allow you to precisely tune the Deville to your trails and style of riding, not what a product manager thinks is right for most people on most trails.