{HEAD ~ a case main body} extending from one lateral side of an internal combustion engine to one lateral side of a rear wheel positioned rearwardly of said engine, said case main body being partitioned into front and rear casing sections and having {TAIL ~ a longitudinally extending lateral wall}, said rear casing section rotatably supporting a wheel axle of said rear wheel and having a recessed portion for partially housing a reduction gear means which includes said wheel axle, an unput shaft, and a gear train operatively interconnecting said input shaft to said wheel axle, 
{ HEAD ~ a case main body } extending from one lateral side of an internal combustion engine to one lateral side of a rear wheel positioned rearwardly of said engine , said case main body being partitioned into front and rear casing sections and having { TAIL ~ a longitudinally extending lateral wall } , said rear casing section rotatably supporting a wheel axle of said rear wheel and having a recessed portion for partially housing a reduction gear means which includes said wheel axle , an unput shaft , and a gear train operatively interconnecting said input shaft to said wheel axle ,
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH