Silkolene Comp 4 10W-40 Synthetic Based Engine Oil. Silkolene Comp 4 is a Synthetic Ester Based Engine oil. It ensures the engine delivers extreme performance and provides complete protection.Developed and designed on the race track for full on racers or weekend cruisers.Formulated to meet the needs of both air and water-cooled 4-stroke engines, Comp 4 10W40 XP is the recommended SAE grade for many motorcycle manufacturers.Specification: API SL JASO MA2 APPROVED Up to 11% Fuel Savings. Up to 18% Lower Oil Consumption. Up to 3% Improved Power (BHP/TORQUE). 1L Bottle.