Rock Oil Castor Kart 100. Air cooled 2 stroke Kart engines present a unique and difficult challenge. The difficulties are caused by the high revs/ up to 20,000 rpm causing extreme inertia loads on the bearings and a mean piston speed that without complete lubrication would create intense temperatures leading to an oil breakdown and eventual seizure.Castor Kart 100 contains a high proportion of synthetics.Benefits: Reduced carbon deposits, resulting from its clean burning characteristics.High shear stability, even under the severest conditions.Prevention of oil induced piston seizure due to its high lubricity.Complete absence of lacquer, gumming and ring sticking.Extremely low rates of wear.Increased engine reliability.Caution: Will not mix with mineral or synthetic lubricants.