Abstract: A sealed bearing assembly for supporting a rotating shaft and, in particular, a crankshaft of a two-stroke engine includes an inner race, an outer race and a plurality of roller elements disposed between the inner and outer races. A grease seal is disposed between the inner and outer races and spaced axially outward from the roller elements along an axis of the bearing assembly. The grease seal includes a rigid support structure and a flexible sealing member attached to the rigid support structure. The flexible sealing member includes at least one sealing lip, which contacts a surface of the inner race to provide a sealing engagement between the grease seal and the inner race, thereby retaining lubrication in an interior of the bearing from escaping at least to an interior of a crankcase of the engine and sealing at least the interior of the bearing against crankcase pressure variations in the engine.

Abstract: An internal combustion, two stroke engine is disclosed. The engine includes a crankcase with a cylinder adapted to house a piston. At least one transfer duct communicates the crankcase to the cylinder. At least one fuel injector is disposed through a wall of the transfer duct. The fuel injector is positioned to inject fuel tangentially to the cylinder.