Billet Clutch Housing CNC machined from 7075 T6 aircraft grade aluminum. By swapping out the cast aluminum clutch housing from our Manual Clutch kit with our new billet offering, all limitations of engine size and RPM limits on the Manual Clutch Kit are removed. The Manual Clutch Kit can now effectively be used on all large displacement engines such as our 108cc or 117cc kits as well as other brand big bore/stroker kits. Inner rotors can also be used. This is a great alternative to the $600+ plus manual clutch kits offered by other manufacturers at a fraction of the cost.