BOS Suspension has released a new Deville 35 fork for the all mountain category. It will initially be available with travel between 150-170mm (fixed) in 27.5 wheel size for the boost 110x15mm standard and is 110 torque compatible. Significant effort went into weight reduction, optimizing stiffness, and creating a highly tunable feel intended for long descents and high speed fun. Claimed weight is about 4.2 pounds. Pricing is TBD.
The Deville offers both low and high speed compression and single rebound adjustment. An inertia valve, dubbed the frequency control valve, is utilized to smooth out sharp edges. The Deville also contains a new monotube damper cartridge, utilizing a coil spring piston to improve reliability, making the rate more linear through the travel and decreasing changes due to temperature.
The low speed compression adjuster controls the fork sensitivity on the trail, while the high speed compression meters the oil flow through the compression circuit. A shim stack is also found on the compression piston to provide support and shape the damping curve. A Rapid Platform Adjustment switch is found outside the HSC/LSC dials, which closes an orifice in the compression oil path to quickly firm things up.
The air spring used in the Deville is different from those found from other fork makers. Riders typically need to push the fork part way into its travel for an orifice to open and allow air flow. BOS took a different approach, allowing this to occur at zero stroke. Additionally, BOS chose to allow the rider to tune the spring curve by providing three different volume limiters for the negative air spring. This should significantly change the sensitivity of the fork, while having similar behavior in deep travel.
A hydraulic rebound stop is utilized on the Deville, slowing rebound as the fork gets deeper into its travel. This will battle against the higher spring rate found in that zone. Additionally, this system acts as a hydraulic bottom-out during the last 15mm of travel. That system is used in conjunction with a reactive foam to provide a bottomless feel.
Lastly, BOS minimized chassis weight by redesigning the crown and lowers. The hollow crown maximizes the strength to weight ratio while providing a stiff frame. Lowers are constructed from magnesium and utilize varying thicknesses based on where strength is needed and to retain the bushings. The combination of 35mm stanchions, optimized crown and lowers should create a rigid frame for the Deville’s new damper to work within.
Here is a video showing the new Deville from the BOS Suspension facebook page:
For more information visit www.facebook.com/BOSsuspension.
This article is part of Mtbr’s coverage of the 2017 Sea Otter Classic in Monterey, California. For more from Sea Otter CLICK HERE.