Outboard drive transmission system

摘要

A transmission for a counter-rotational propeller system of a watercraft outboard drive provides an increased flow area for exhaust discharge behind the transmission within the lower unit. The transmission includes a pair of counter-rotating gears. A front clutch selectively drives an inner propulsion shaft by engaging the front gear. A rear clutch selectively drive an outer propulsion shaft by engaging either of the gears. The front clutch lies forward of the front gear and the rear clutch is interposed between the gears. The clutching mechanism thus entirely lies forward of the rear gear to provide more space for exhaust discharge flow behind the transmission.