Takegawa 138cc Twin Cam Desmo 4 valve bore and stroke kit for the highest level of design and performance available for the Honda CRF50 CRF70 and 12V Monkey bikes. Desmo valvetrain 4 valve twin cam head, 57mm forged aluminum SCUT piston and all aluminum cylinder kit, Takegawa specially treated long stroke 54mm crankshaft with oversize bearings, patent pending oil jet cooling and lubrication system are all included in this top of the line bore and stroke kit. Available in 2 point and 3 point support crankshaft.