Compression - Dirt 39/30 2C 17 2017 Showa CRF 450R - FMGV 391201
Gold Valves have been around for many years now and have been proven time and time again to be successful in providing desirable suspension outcomes.Many races and in fact, championships have been won on the back of Gold valve performance.
The design philosophy is simple ..tunability.
All suspension tuners will attempt to manipulate oil flow within forks and shock absorbers to achieve greater levels of performance. A very basic adjustment would be to simply alter oil viscosity for a desired effect. Next step beyond oil weight change is to revalve the suspension components. A valve assembly consists of two critical parts. The valve body (or piston) and the shimstack. The shimstack consists of thin metal discs made from spring steel, which are generally of varying thicknesses and diameters. Usually they are configured in a tapering stack to form what could easily be described as a type of leaf spring. The shimstack is designed to place a spring force against the oil flow creating damping. By altering the quantity, diameter or thickness of the shims the damping rates can be adjusted to better suit the demands of the rider. The limitation with simple revalving however is that the tuner is limited to the parameters of the stock piston design.
By replacing the stock piston with a Gold Valve we can now exceed those limitations and extend our tuning capability. When it comes to manipulating oil flow, piston design is key. The very force that a shimstack will experience is determined by the dimension of the piston port area.
- Increase the port area .increase the force / reduce maximum flow velocity.
- Decrease the port area .decrease the force / increase maximum flow velocity.
Larger ports are desirable where less progression is required. Smaller ports for more progression. Progression is a word whose sound is better than its meaning. We all like the sound but in fact we can get too much of a good thing. To progress simply means to transition from one state to another. In suspension terms we transition from soft to hard. If damping is too progressive we will experience a lack of initial control followed by extreme harshness very soft to very hard.
Gold valves come in a range of flow rates to enable any tuner to achieve the most appropriate outcome for the rider.