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Rear fork pivot bolt worn

markm

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Any information would be appreciated, I took the swing arm off yesterday and found that I have play in my bolt through the swing arm. After cleaning it up and looking it over the place where it rides in the bushings I believe is worn on one side on both ends where it should be a tolerance fit. The largest part of the machined bolt is 14.16mm and one side it only measures 13.7mm The rest of the bolt is 14.0mm My rear fork pivot bolt is worn and would like to replace it with a new or good one. Does any one sell a replacement bolt? Im sure if I buy one from ebay it will most likely be worn also. Probably not many sellers are looking at it to see its worn only if the chrome is good.
 
After further looking at my bolt I do not think that the bolt is worn where it rides on the bushings but I do think now the bushings are worn.
 
The bolt MUST be worn at the bushings, that is the only thing that can wear it. And if bolt is worn the bushings for sure will be, they commonly wear at 5X the rate since they are softer and intended by that to do so. Of course someone could have changed the bushings and not the bolt in the past, what is usually done.

Bolt can be worn at the frame holes too if not tight enough to cinch it up solid there.
 
Pretty much need none on bolt, the visual is enough to determine.

The bolt does NOT wear on that one and my bad. There is a long bushing that moves inside the shorter swing arm bushes, the bolt then runs through all of them and locks the whole thing to the frame. If the bolt itself has wear then it was loose and twisting in the frame, it should not. Supposed to lock the long bushing in the frame and then that long one and the short ones in arm wear.

You have wear specs on both the long and short bushes.
 
Last edited:
what do you mean by collar? I got this picture from the web
 

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Thinking it will by OD but maybe not by length.

Pic is flawed too, '79 DOHC uses bushings and '80-later use needle bearings, IIRC the bearings are bigger in OD.
 
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