Another quality problem?

L

Liteway

expert rider
Joined
Nov 11, 2022
Messages
109
Location
Choctaw Okla.
The shift lever fits so loosely on the shifter shaft that even when tightening the bolt until it bends, it still does not pinch the shaft enough to prevent slop.
My Yamaha has a tighter fit without even fitting the retention bolt. A real world demonstration of loose tolerances?

Anyone else have this problem?
Suggestions?
shifter-shaft.jpg
 
I have a dubious solution
PXL-20230206-181851933-shaft-slop-solution.jpg


This forced the gap to close more evenly and tightened the lever to the shaft.

I then tried using a sliver of .060" aluminum in the gap but that did not work. Then some .040. This worked a little but not so good as the dime.
The dime measures .045. I just cut that in half and used it.
10 cent solution.
 
Liteway said:
I have a dubious solution
PXL-20230206-181851933-shaft-slop-solution.jpg


This forced the gap to close more evenly and tightened the lever to the shaft.

I then tried using a sliver of .060" aluminum in the gap but that did not work. Then some .040. This worked a little but not so good as the dime.
The dime measures .045. I just cut that in half and used it.
10 cent solution.
Click to expand...

I haven't noticed this on mine but I will check it.
 
I will investigate 👀
I have noticed there’s a little play somewhere and that the quick shifter adjustment is sensitive to different shoes.

Edit: Nothing strange here.
 
Last edited:
I confirmed the shift lever on my 401 has plenty of slop despite the pinch bolt being tight. This definitely should not be the case.

I'll try the spacer to see if I get the same results as @Liteway .

Thanks for pointing this out, a bit disappointed this is the case with a new bike.
 
JJCool said:
You will need to shim the shaft not the gap in the lever, to tighten things up. Take the lever off. Expand the gap a little with a flat screw driver. Add a wrap or two of aluminum foil around the shaft. Reinstall the lever. I know its a bodge, but it works.
Click to expand...
Then you found your shift lever loose as well?

I thought I made it clear that shimming the gap, with just the right thickness and placement of a shim was tried and proven, it's not a theoretical fix.
It takes much of the bending force off the pinch bolt. The bending causes binding which can lead to possibly stripped threads or a twisted off bolt head.

No doubt the method you describe works fine, ( I assume you have tried it) but as is often the case , there is more than one way to skin a cat.
 
Last edited:
Yours does not look much out of the ordinary. If it were a problem it would look like my photo in the initial post on this thread where the bolt is visibly bent in trying to get it to cinch up.
It's likely to vary from bike to bike as you would expect with sloppy tolerances.
Or maybe there has been a production change along the way.
 
After re-visiting this issue, I went back and verified that a dime would fit loosely within the gap AND there is slop on the lever. the bolt holding the lever at this point is plenty tight.

After tightening the bolt on the lever some more to where a dime will not fit in the gap, I proceeded to re-check the lever for slop. at this point the lever is tight on the shaft with NO slop at all.

The moral of the story is that one may have to tighten this lever more than they normally would to keep it tight on the shaft. I really think the tolerance from with the splines on the shaft and the engagement splines on the lever are too loose.

@Liteway I think the most permanent solution you may have would be to order a new lever and hope that the tolerances are better where you don't have to use a shim. The other option I have seen on YouTube is people with Duke 390's with the same issue, they widen the gap for the slot on the lever and reinstall on the shaft to correct the issue.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom