As the owner of a Twin Cam 88-powered Harley-Davidson motorcycle, it is your job to ensure that the engine, primary clutch system and transmission receives regular fluid changes. Unlike a unit-construction motorcycle, which combines its engine and transmission into one assembly that uses a single type of oil, Harley’s Twin Cam engine is a separate item from the transmission and clutch. Each system uses its own oil type that needs replacement every 2,500 miles.
Warm up your Harley-Davidson motorcycle to bring its fluids to operating temperature. Start the motor and let it idle for at least 3 minutes, then turn the motorcycle off. Let the oil settle for another 5 minutes.