Suspension - Fork Damper Design

DIAGRAMS                               Suspension fork design is varied, triple clamp, single crown, upside down, right side up, reverse arch, multi pivot, mono strut etc. Considered part of the bicycle chassis the front wheel is attached to the bottom of the fork, with a steerer tube attached at the opposite end, the fork structure must be constructed in such away that avoids flex in all directions, while maintaining a smooth action as it absorbs bumps and under braking.   Most suspension fork dampers are a based on a cylindrical tube design, either a fixed compression rod with a valve attached passing through the actual fork stanchion ( the inner walls honed to accommodate the valves outer surface as the stanchion moves up and down ) or a fixed cartridge that’s sealed with a compression rod that cycles a piston through a separate oil cavity, some cartridges are open, utilizing the fluid that lubricates the forks internals, some are closed, with some designs using an internal floating piston to facilitate displacement, or a rubber lung that expands and contracts to aid oil volume change during the forks operation, or Through shaft dampers where oil displacement is balanced due to equal shaft mass of the compression rod moving through both ends of the cartridge. Other fork damper designs use fixed tubes with staggered and varying hole diameters that resemble a flute, the stanchion passing over the tube creating variable oil flow on compression and rebound. Past designs have used air regulated through orifices, or the main spring material that was promoted as containing damping characteristics ( Elastomers ) or low end suspension forks that use only steel coil springs with no damper at all, although these still appear on budget bicycles with limited travel.   MTB suspension now equals the motor industry, with complicated but necessary internals specific to the bicycle and the pilot, constructed with weight, performance and durability against harsh and challenging conditions, today’s bicycle suspension is the greatest advancement since the invention of the bicycle itself.   Like any well designed suspension damper oil is used, flow is regulated through valves, oil ports, shimmed pistons, gates and needle orifices, bump or spring energy is absorbed and the heat produced dissipated in the oil. One advantage over rear shock dampers is a suspension forks size, larger oil volume and increased shock stroke without the need for complicated linkages that multiply wheel travel from the compact design of a rear shock, although having mentioned that, Foes 5 inch Curnutt rear shock surpasses the 2 inch travel forks of early suspension platforms.