5 speed trans shimming

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515moto
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Joined: Mon Jan 19, 2026 6:02 pm

5 speed trans shimming

Post by 515moto »

Hi all,
Following much written and video instructions I carefully and I think correctly determined end play gap and therefore the needed shimming. To get to .005" (my target) I need what seems like a lot of shimming! 42, 53 and 56 thousandths are needed. So, for those who have done this, is this a lot? I did have to replace the cover with one sourced from ebay so it is not the original cover. Hmm. Thoughts anyone?
Rob Frankham
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Re: 5 speed trans shimming

Post by Rob Frankham »

It does seen quite high but, if that's what it takes, then thats what you need to use. If you're completely satisfied with your measurements than go for it, but I would be inclined to do the math again just to check. That being said, if the shims are too thick, the gearbox will be tight once the cover bolts have been tightened down. If this turns out to be the case, then you need to re-visit the whole procedure.

Rob
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515moto
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Joined: Mon Jan 19, 2026 6:02 pm

Re: 5 speed trans shimming

Post by 515moto »

Thanks Rob. The measurements were careful and the math was done 2 different ways twice with the same final result each time. I guess I need to source a few more plus-size shims. My collection will not do the job!
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gspd
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Re: 5 speed trans shimming

Post by gspd »

FWIW. I aim for zero clearance without the gasket.
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515moto
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Re: 5 speed trans shimming

Post by 515moto »

Hi. I measured with the gasket in place.
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SteveD
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Re: 5 speed trans shimming

Post by SteveD »

I have a copy of Airbear's (Charlie) excel file for recording and calculating shimming. He's kindly given permission to forward it to anyone in need.
I'd need a pm with an email address as the forwarding system here doesn't seem to allow an excel attachment.
Cheers, Steve
Victoria, S.E.Oz.


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1994 R1100GS.
Rob Frankham
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Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
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Re: 5 speed trans shimming

Post by Rob Frankham »

SteveD wrote: Sat Feb 21, 2026 9:58 pm I have a copy of Airbear's (Charlie) excel file for recording and calculating shimming. He's kindly given permission to forward it to anyone in need.
I'd need a pm with an email address as the forwarding system here doesn't seem to allow an excel attachment.
Hi Steve,

I'd be interested in seeing that. I have my own version and it would be interesting to see his approach (and whether the results are the same...) :D

Will PM an email address...

Thanks

Rob
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SteveD
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Re: 5 speed trans shimming

Post by SteveD »

Sent Rob.edit: not sending. I'v tried 3 addresses and they're all sitting in "drafts". :arrow:
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
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