AHP 4 speed 1 down 3 up transmission, hardened gears and shift forks. This transmission kit is made for those wanting to upgrade their stock Honda motors from a 3 speed to a 4 speed. AHP's transmission kit will work with both semi-auto and manual clutches and will fit into a OEM Honda bottom end. Will also fit import motors. Good for 50cc through 108cc builds. Set comes complete with main shaft, counter shaft, shift drum and shift forks. Primary reduction ratio: 3.722 Gear Ratio: 1 - 3.182 2 - 1.706 3 - 1.238 4 - 0.917 FREE Priority mail shipping inside the USA. Transmission kit is brand new in box.