DIRECT LEVER OVERHEAD VALVE SYSTEM

摘要

An overhead valve engine including a cylinder bore having an outer end; and a crankshaft assembly including a substantially straight crankshaft, a substantially cylindrical journal eccentrically mounted on the crankshaft, a one-piece connecting rod rotatably mounted on the journal, and a counterweig ht mounted on the crankshaft. The engine also includes a cam shaft having at least one cam surface and an axis inward of the outer end of the cylinder bore; two valves having opened and closed positions; two valve stems, each valve stem being attached to a valve; and two generally L-shaped and pivotab ly mounted valve operating levers (168, 172), each lever including a first leve r arm having a cam follower in contact with the cam surface, a pivot axis abou t which the lever pivots, and a valve arm in contact with a valve stem, where movement of the lever caused by the cam surface causes the lever to pivot an d the valve arm to depress the valve stem and thus open the valve.