The bolt-on big bore kits from Faito are race tested before being sold, you can have confidence using them on your engine. This bore up kit for the Honda C100EX Cub Dream and Honda Wave100/Dream/Astrea/Citi/Supra/Biz 100 underbones. (49.5mm stroke, horizontal cylinder cooling fins) Increases your cylinder bore from 50mm to 53mm, giving you a higher engine displacement of 110cc (111cc). Professional installation is highly recommended! A tune up and fueling adjustments are required after installation!