For the most demanding riders, Takegawa introduces the 124cc Twin Cam Desmo 4V bore and stroke kits for the CRF50 and Monkey bikes. 54mm bore x 54mm stroke with 12.5:1 compression ratio. Available in standard two point support as well as 3 point support crankshaft. Takegawa 54mm race crankshaft is designed with oversize 22mm inner diameter bearings to further enhance strength and durability beyond the limits of other manufacturers.