50cc QMB139 4-stroke 50mm, Non Emissions Cylinder Head with 69mm Valves for use with 81.3cc Big Bore Kit! (See Related Items)*You may need to modify your engine case to accommodate the larger cylinder.
50cc QMB139 4-stroke 50mm, Non Emissions Cylinder Head with 69mm Valves for use with 81.3cc Big Bore Kit! (See Related Items)*You may need to modify your engine case to accommodate the larger cylinder.