The compressor shaft facilitates engine starting, especially in powerful engines. It temporarily reduces the pressure inside the cylinders during the starting process, which is achieved by slightly opening an exhaust or intake valve. When the engine reaches a certain speed, the compressor automatically disengages, allowing the valves to function normally and the engine to operate at full compression. With regular maintenance, oil changes, periodic checks, and proper use, the compressor shaft can operate for many miles. The compressor shaft relieves internal engine pressure, allowing the motorcycle to come to life smoothly and reliably with every start.