Kitaco's biggest and best 2 valve cylinder head to date for the CRF50. Massive 29mm intake valve, 24.5mm exhaust, with stronger "waist" type stems at 5.5mm diameter tapering to 4.5mm for maximum strength and light weight. Compatible with either standard SE-Pro camshaft or auto-decomp. This is the head and assembled valve-train only. No covers included. May require longer cylinder studs from the SE-Pro kits.