Athena Aluminium Racing 50cc Cylinder Kit for geared motorcycles with the Minarelli AM6 engine. The Minarelli AM cylinder kits with its exhaust valve could be seen as a mini revolution. Thanks to the variable timing, the cylinder has its full power available in a much wider power band. A valve has been placed in the exhaust port that adjusts its position to match the timing. It has long been the standard in motocross and enduro, giving 2-stroke engines the best possible performance anywhere in the rev range. The manufacturing quality of these cylinders is very good and all necessary parts for assembly are included. Along with the piston and gasket set, there is also the complete reed valve assembly. If you are looking for top performance, you have come to the right place! An installation manual in Italian, Spanish and English is also included with the cylinder kit.