Power transmission mechanism for motorcycles

Claim 1

A power transmission mechanism for a motorcycle, comprising a transmission casing having a wall provided with an opening therethrough; a change speed gear mechanism mounted in said transmission casing and including a countershaft having one end projecting out of said transmission casing through said opening; a driving bevel gear formed integrally on the projecting end of said countershaft; a final gear case including fasteners detachably fixing said final gear case to said transmission casing; axially spaced bearings supporting said countershaft within said transmission casing; a first bearing holder mounted in said opening and secured to said final gear case and engaging one of said bearings; a second bearing holder engaging the same bearing and carried by said final gear case; a final shaft rotatably mounted in said final gear case and having a driven bevel gear integrally formed therewith and meshing with said driving bevel gear; a final shaft bearing mounted within said final gear case; said final gear case, said bearing holders, said driving bevel gear, said countershaft, said driven bevel gear, said final shaft and a plurality of the gears on said countershaft of said change speed gear mechanism being separable from said transmission casing as a unit with release of said fasteners.