1000二代倒挡器：800cc reverse gearbox

一、技术参数 → Technical parameters
规格 → specification
速比 → ratio
连接花键 → splined joint
输入（内）花键：input spline
矩形花键：rectangular spline
输出（外）花键：output spline
矩形花键：rectangular spline
适配发动机：adapter engine