Zongshen CG250cc engine 72.5mm Big Bore Kit (Hawk, XPRO, TaoTao, Apollo, SSR)

  
We will respond within 24 hours, although response time is generally within an hour. IT IS THE CUSTOMERS RESPONSIBILITY TO CONFIRM COMPATIBILITY WITH THEIR ENGINE BEFORE PURCHASING. Zongshen 250cc engine 72.5mm Big Bore Kit is a product designed to enhance the performance of motorcycles and scooters from various brands such as Hawk, XPRO, TaoTao, Apollo, and SSR. The kit includes a larger piston and cylinder to increase the engine displacement, resulting in improved power and torque. This product is specifically designed for Zongshen or similar CG250 brand engines and is compatible with various models. You can expect a substantial gain in bottom end torque, and around 5-10mph top end (this varies greatly depending on rider weight and specifically with what other mods you have). IMPORTANT-this will not fit a the 2023 and newer Hawk 250 X-Pro models. This kit has a 16mm wrist pin.

Please ensure that your engine has a 16mm wrist pin before purchasing. This kit is for 16mm wrist pins only! If your Hawk 250 has a counterbalance shaft on the engine then it likely has a 15mm wrist pin.

This is a complete top end Big Bore rebuild kit, with 72.5mm piston, piston rings, pin clips (Circlips), 16mm wrist pin, valve stem oil seals, exhaust and head gaskets. Some newer model CG250 engines might have a smaller crank case bore diameter than previous models, requiring minimal machine work. Turning the cylinder sleeve down to 75mm and/or opening/cleaning up the crank case diameter. However, the bottom end gain is well worth it, especially if you are looking for big torque gain.

Although rare, some CG250 models have a 15mm or 17mm pin- (these engines are usually the "knock off CGs") this kit WILL NOT fit those models.