83mm Cylinder Unit Kits for 400cc Mountain Lion JS400 JS183FMQ ATV Quad.This kit includes a cylinder, piston, rings, wrist pin, and necessary gaskets for a complete rebuild.Designed to fit 400cc models with the JS183FMQ engine, it provides a precise replacement for worn or damaged components.The cylinder is machined to standard specifications to ensure proper fitment and performance.Compatible with stock bore dimensions and suitable for routine maintenance or engine restoration.