Why burn daylight fiddling with a finicky motor? Take the easy way out, with an engine that's as powerful and dependable as the day is long: LA-Series engines from O.S. are flier favorites because they are easy: easy to afford, easy to run, easy to maintain — and hard to beat for powerful, dependable performance. That's because O.S. has worked hard to make them that way. With CNC-machined parts, for precise fit and finish. Heavy “webbing” on one-piece crankcases to resist distortion and prevent binding. A tall heat sink head and crankcase fins so LA engines cool better and last longer. And with nylon backplates that include an integral, molded-in fuel inlet and needle-valve holder.