Takegawa 107cc S-stage bore kit for the Yamaha TT-R50 is the perfect power boost keeping economy in mind. 53mm piston, all aluminum lightweight cylinder, and sport camshaft for stock head are all included in this easy to install top end kit. Also available in a combo kit with Keihin PC18 carburetor, throttle cable, filter, intake manifold, and 31T rear sprocket to help you put the power to the ground.