THESE PARTS ARE MOSTLY FOR Z50 XR50/70 CRF50/70 ATC70 CT70 AND TRX90'S @ COMPONENT ENGINE PARTS_ONLY @ ENGINE_KITS @ CARBURATION AND INTAKE @ ELECTRICAL UPDATES @ EXHAUST @ SUSPENSION PARTS @ INFO_ON_FITMENT AND_INSTALLATION @ BORE_X_STROKE FIND_YOUR_CC's CLICK_HERE @ KNOWN TRANNY GEAR RATIO'S @ STOCK GEARING AND CHAIN LENGTH 50CC TO 350CC @ NEW !!! SOME TECH INFO @ METRIC BOLT THREAD PITCH