4-speed main shaft drive gear, spacer mod.

[poorbiker]

Well since my engine is tore down for repairs I thought I would take this opportunity to tear down the trans and do some improvements. Some years ago I replaced some of the gears and shift forks, fork shaft, counter shaft, with Andrews and while replacing parts I had noticed the main gear shaft and main shaft drive gear, were looking a little weak, they were original. Also the spacer looked pretty worn and the seal was leaky. Got a new spacer, seal, main shaft, main shaft drive gear, all Andrews. Found main shaft drive gear bushing badly worn. Also found the key sheared off on the starter clutch shaft, guess the taper kept it tight.

Anyway I put new gear drive in lathe and with a rounded bit of the right size deepened the existing groove to except an o-ring, then placed the spacer in lathe and put a 30 degree angle cut on outside about .025 deep to except o-ring, then test fit pieces.
Seems like this is going to work very well, got the idea from an article I read, same article talked about installing needle bearings in the starter cover in p[lace of the bushings, have the bearings going to install them also.

Does anyone have some other trans mods/improvements they have done.........

[Jerry Wieland]

I've bored out hi gear and put needle bearings in like HD 5 speeds did. I mainly did it because the bushing had spun and ruined the id of the gear but it works good. Especially on the late 4 speed with the lousy hi gear setup.

Jerry

Well since my engine is tore down for repairs I thought I would take this opportunity to tear down the trans and do some improvements. Some years ago I replaced some of the gears and shift forks, fork shaft, counter shaft, with Andrews and while replacing parts I had noticed the main gear shaft and main shaft drive gear, were looking a little weak, they were original. Also the spacer looked pretty worn and the seal was leaky. Got a new spacer, seal, main shaft, main shaft drive gear, all Andrews. Found main shaft drive gear bushing badly worn. Also found the key sheared off on the starter clutch shaft, guess the taper kept it tight.

Anyway I put new gear drive in lathe and with a rounded bit of the right size deepened the existing groove to except an o-ring, then placed the spacer in lathe and put a 30 degree angle cut on outside about .025 deep to except o-ring, then test fit pieces.
Seems like this is going to work very well, got the idea from an article I read, same article talked about installing needle bearings in the starter cover in p[lace of the bushings, have the bearings going to install them also.

Does anyone have some other trans mods/improvements they have done.........

[BigLakeBob]

I bore the starter cover on the outside and put in lip seal CR7443, then gang both bushings to the inside. Oil gets to both bushings and dirt doesn't enter at all. The washer hides the seal and nothing can be seen.