Shifting noise

[UNCLE WILLIE]

my service manual shows no helial gears anywhere in 010 year..that has nothing to do with gear clunk noise anyway .. like mentioned before bike transmissions have constant mesh gears and a drum rotates to slide shift forks that lock and unlock pairs of gears when u shift .. there are no synchronizers .. there are 5 square [dogs] on one gear that slam into holes on another gear while spinning .. its a mystery to me how they work as good and quiet as they do .. when I ask the head guru at the shop here why so much noise he said its because of the size of the gears [big] and the neutral position it has to pass through from 1-2 or 2-1 which makes the most noise .. it feels like a spring loaded detent that locates neutral but the manual doesn't show it..all in all I haven't found anything that will dampen the noise . but it is quiet when cold and oil is thick but we cant use STP or 90 wt .. clutch fluid has nothing to do with the noise but should be kept clean for obvious reasons