Bel-Ray® Thumper Gear Saver transmission oil is a premium 4-stroke transmission oil that has been developed for the unique demands of 4-stroke motorcycles equipped with separate engines and transmissions. Formulated with extra protection for gears and bearings subject to high torque loads of today's powerful 4-stroke thumper engines. This multi-viscosity formula flows freely for better clutch cooling and provides positive clutch engagement for better starts and longer clutch life while protecting highly-loaded gears from wear, ensuring smooth shifts for more positive action. Developed for the unique demands of 4-stroke motorcycles equipped with separate engines and transmissions. Formulated with extra protection for gears and bearings subject to high torque loads of today's powerful 4-stroke engines. Multi-viscosity formula flows freely for better clutch cooling and provides positive clutch engagement.