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 with the crank mounted clutch. Recommended for engine builds up to 117cc.

Set comes complete with main shaft and gears, counter shaft and gears, 15t front sprocket, shift drum and hardened shift forks complete and installation diagram. Will be shipped assembled for you!

The AHP 4 Speed Transmission Kit uses a Honda Z50 sprocket which is NOW INCLUDED with all transmission kits from 9/22/08.

Primary reduction ratio: 3.722

Gear Ratio:

1 - 3.182
2 - 1.706
3 - 1.238
4 - 0.917

Youtube Video of case splitting to install transmission: