Tuning Kit 85cc for 50cc 12V Head

This kit is for 12Volt engines with a 12Volt 50cc cylinderhead (GK4).
Steel cylinder: 63mm long and with 51mm bore.

This kit works fine with a 20mm -24mm carb.

We recommend to use this kit with a stronger oilpump.

This kit is marked with 49cc

This set will fit all 12-volt (GK4) engines such as ZB50/XR50/ST50
which are still using the original 50cc 12-volt cilinderhead (GK4).
Will also fit most chinese 50cc aftermarket engines with stock head.