Takegawa customers with XR100R CRF100F Superhead bore kits can upgrade to full +R Superhead performance with these version up kits. Two version up kits with choice of camshaft. The +R Superhead utilizes the Stage 3 piston from the old Superhead kit. If you have a Stage 1 or Stage 2 115cc, 120cc, 124cc, or 130cc Superhead kit, you will need to also purchase the piston kit separate from the version up kit. Customers with Stage 3 Superheads, and Stage 1 or 2 SCUT 125cc or 136cc kits can maintain their OEM piston if still within operating tolerances.