The Greased Lightning is Horstman's 3 1/2" size 4 stroke twin disc clutch. Horstman is the originator of disc clutches in karting in 1977. The Greased Lightning came on the scene in 1995 for use with the flathead B&S engine in stock and superstock classes. Still popular today for the Raptor and clone engines where rules permit. Available for the tradtional #35 chain or the lighter #219 chain. #219 is not permitted in 4 stroke oval track events except specific outlaw events. Features lightweight aluminum drum with patented steel clips for wear bars against the friction disc tabs. Cam action levers for uniform pressure and total lock up. Adjustable stall speed for custom tuning.