CLEANING A KTM 65SX POWER VALVE

and Husky TC65 have a pneumatically-operated power valve, meaning that the valve in the exhaust port is rotated by pressurized air coming from the expansion chamber rather by than a mechanical system from the crankcase. When the exhaust pressure rises, the pressure travels through a hose connected from the expansion chamber to a diaphragm which turns the power valve in the exhaust port raising the roof height