Gearbox rebuild tips

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baz

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It's been at least 15 years since I rebuilt the gearbox on my commando
I replaced every bush / bearings etc including the layshaft roller bearing conversion and a Steve maney outrigger
But the gearbox is in need of another rebuild
The Kickstart is moving under exelleration
It's noisier in second gear
It doesn't like going into first gear
And it's generally tight to change gear, tighter than it was anyway
I'm looking for tips for the above problems
What's causing it to not want to go into first? Sometimes it feels like it's in and it jumps out at the most inoportune moments
I assume the layshaft roller bearing is knackered as the kickstart is moving etc?
Any help on building this box better would be appreciated
I do ride the bike very hard hence the outrigger
Just trying to save a bit of down time when I pull the gearbox cheers
 
Primary chain tension and clutch would be on my list to go at first.

Also look at fitting a needle roller inside the kickstart shaft instead of the bush, you only need to modify the layshaft.
 
Primary chain tension and clutch would be on my list to go at first.

Also look at fitting a needle roller inside the kickstart shaft instead of the bush, you only need to modify the layshaft.
I run a belt drive ,I thought I ran it on the loose side but it's something I can easily check
I've not seen the needle roller conversion? Sounds interesting
Cheers
 
Yes Ive often wondered whether that was worth the bother other bikes besides Commando use a bush
yet Ive never seen it actually done.
 
Needle roller

SCH1016B Needle Bearing 5/8"x7/8"x1" inch

Straight replacement inside the kickstarter shaft of the bush, layshaft that runs inside the kickstart shaft needs grinding down to fit.

When my Portuguese layshaft bearing was replaced in the late 80's I did the needle roller at the same time as the bush was worn and the gearbox has not needed touching since.
 
Needle roller

SCH1016B Needle Bearing 5/8"x7/8"x1" inch

Straight replacement inside the kickstarter shaft of the bush, layshaft that runs inside the kickstart shaft needs grinding down to fit.

When my Portuguese layshaft bearing was replaced in the late 80's I did the needle roller at the same time as the bush was worn and the gearbox has not needed touching since.

Interresting! About grinding down the layshaft, there´s no risk of removing the hardened surface on the shaft? I also wonder if there´s a fix to solve a bad fit of the steel shaft bush in the inner cover? My new bush is not tight in any way, falls right out if you turn the cover around..... Will it be good enough to use a good bearing retaining compound?
 
I have never took my gearbox apart to look at the layshaft to see if the hardening is still there but if it was an issue there would be symptoms such as the kickstart moving down and there is no such evidence. You take 60 odd thou off the diameter which takes off the scroll and leaves a hardened surface.

I would use loctite on a outer cover kickstart bush.
 
I have never took my gearbox apart to look at the layshaft to see if the hardening is still there but if it was an issue there would be symptoms such as the kickstart moving down and there is no such evidence. You take 60 odd thou off the diameter which takes off the scroll and leaves a hardened surface.

I would use loctite on a outer cover kickstart bush.

Thanks for the info, will absolutely look in to this!
 
Instead of grinding down the end of the layshaft - open up the inside diameter of the bearing.
 
You have to grind the layshaft to remove the scroll groove.
Doing so isn't weakening the shaft? Is there a no scroll shaft available? Baz uses a Steve maney outrigger...very interesting. Still available?
 
Doing so isn't weakening the shaft?

Is there a no scroll shaft available?

If it does then not so much to be an issue as mine was done nearly 40 years ago and is still working. It is only 60 thou on diameter.

Never seen an unscrolled shaft but then I have had no issues grinding it off to spend any time looking
 
Doing so isn't weakening the shaft? Is there a no scroll shaft available? Baz uses a Steve maney outrigger...very interesting. Still available?
I have given up with the maney outrigger
It's broken again through fatigue I believe,I have welded it up and made sure it's under no stress when tightened but it broke again at the top so I've given up with it
If I ever get time I will re make it from steel
Cheers
 
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