Airsal 88.3cc is the largest and most powerful big bore kit available for the 50cc 2-stroke market. Top quality with Vertex pistons and serious power delivery at an unbeatable price. For extreme tuners. The cylinder should be run with a relevant exhaust system and a 21mm carburetor. Requires 45mm stroke crank. The 45mm stroke and 50mm bore give this cylinder its capacity. Not for inexperienced tuners, this is a serious high end cylinder.