BOS suspension has a long legacy in the mountain bike world as well as Rally, Motocross, and Dakar. Bringing that experience in other off road categories to DH, the company is now launching an FCV (Frequency Control Valve) in their premiere downhill offering
The system consists of an inertia valve in their hydraulic cartridge, which is able to differentiate between rider and trail inputs.
You can think of it as being a second damper that is able to neutralize compression forces from the rider, which keeps the fork riding higher in it’s travelwhen  needed, e.g. cornering.  On big hits, the FCV can open up to help dissipate impacts.
In addition to being tested on things like Carlos Sainz’ SMG-Redbull Dakar vehicle, this implementation of the FCV valve been in development for over two world cup seasons.
Other changes to the fork include a redesigned chassis and increased travel. To compensate for the added stress generated by 27.5″ wheels, BOS has increased the stanchion diameter from 36mm to 37mm.. They’ve also redesigned the lowers to offer improved tire clearance.
Inside the air cartridge is now independent from the stanchion, which allows the fork to flex, and results in increased sensitivity. They’ve also equipped the new fork with a hydraulic bump stomp that is longer.
Under testing there was a visible transition on the charts when the fork hit the old bottom out system, but this new longer hydraulic bottom out system allows BOS to build in more progressiveness while eliminating that abrupt ramp up.
To accommodate the longer bump stop, they’ve added an additional 8mm of travel. The redesigned Idylle FCV now features 208mm of supple suspension goodness. Weight is claimed to be 2680g and we’re waiting back to hear on final US pricing.
We’ve also been told that the company is also working to integrate the FCV technology throughout it’s product line, so expect a big announcement next year when the 2016 product premieres.
