Big bore for this bike / Yamaha YBR
Kit:http://item.taobao.com/item.htm?id=10300887489 | Piston <fits Yamaha RS100 / Yamaha YBR125/ Honda (Kymco) GY6 125 / Suzuki GSX125 ...> ONLY if u know someone can cut bigger hole locally : http://item.taobao.com/item.htm?id=8536330403