Check the listing for details. Avenger 85cc 52mm Bore 2 Stroke Motorized Bicycle Engine Kit- Beats Phantom 85!. Condition: New. Listed at 199.00 USD. Full Avenger 85 engine kit! True 85cc. Huge ports. Excellent timing. Balanced crank. Designer of cylinder: Ken Hinson/ Kelly Cansler Faster than phantom 85 and more powerful. 52mm piston. Phantom 85 / YD100 killer. Full kit. Game changing engine kit! Shipping cost on eBay is higher than California Motorbikes Specs:52mm bore, 40mm stroke12mm wrist pinNew YD85cc rodMade in the Yuandong Engine Factory, same factory that made the orginal Skyhawk motorsBigger intake compared to phantomBigger exhaust compared to phantomBigger transfers compared to phantomBetter timing compared to phantomLarge exhaust pipe, slightly larger than phantomExcellent casting quality with a heavy, large head that is 100 grams heavier than a stock 80cc headCNC heads availableCools way better than a phantom, even when stock.