Motorcycle rear monoshock gas absorber YSS for Aprilia RSV4 1000 (2009-2014). The shock absorbers YSS Top-Line are equipped with internal gas tank to linear and precise to ensure optimum cooling. Strength, precision and performance are also guaranteed by the steel stem and treated with low friction special Teflon and machining precision. The shock is adjustable for preload by turning the adjustment ring in the spring, return via manual ring and wheelbase of 5mm. Is designed and built to suit the specifications of the model on which it will be installed.