Lower front forks bushing

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DogT

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How loose on the fork tubes should the lower bushings be? I have new tubes and new bushings, and the old bushings would rotate easily. With the new tubes and bushings, one of them is tight, I can barely turn it by hand. Should it be loose enough to rotate easily?

Dave
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it,s the outer dia thats important not the inner However if the inner is badly finished/machined I would surely measure the outer dia .That steel bush is just there to keep them stanchions central in the sliders but sometimes they are a bit oversize with very interesting results when your forks go in all the way....
normally the steel bushes do not need replacing its your sliders that do wear
 

DogT

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Yes, I was thinking about that issue of the steel bushings on the aluminum sliders. I would think AL would wear rather quickly. As far as I know, this front end has about 13K miles on it, and the original bushings (both top and bottom) were hardly worn, I could hardly tell the difference in the old and new parts as far as clearance (however one of the new top brass bushings was out of round, so I can't use it). The tubes however, the chrome was worn off in parts. I still would like to have the one lower bush a bit looser on the tube, and maybe I can just use some Emory cloth to polish it down a bit to get the looser fit. Since they ride in oil, I wouldn't think there would be an issue with polishing off some of the chrome.

Any idea how long the aluminum sliders last in mileage?

Dave
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When a hard and a soft metal rub together it's usually the harder metal that wears first, this is because minute pieces of swarf etc become embedded into the softer matal, which then act as an abrasive on the harder surface,
Dave.
 

Flo

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Do I understand this right? The lower steel bushes should be a tight fit on the stantions (tubes), otherwise having clearance on the tube & the slider will be too sloppy a fit.
 

DogT

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Flo,
I'm not sure anyone said that the bushings should be a tight fit to keep the outside diameter a tight fit in the slider. My main question is "is it important to keep the bushings a loose fit on the tubes or is it ok if they are tight, and thus do not move around, which they will probably not do even if they are loose on the tubes". I'm still not sure that has been answered, but I think I will put some Emory cloth on the tubes to get an easy fit to the lower bushings since the original bushings were an easy fit on the tubes, not tight.

Dave
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DogT — the critical thing is that the stanchion should be able to move up and down smoothly with the new top and bottom bushes fitted but also with the minimum amount of side play. As far as I can see, the steel bush does not need to float on the stanchion, it just has to do its job of supporting the stanchion as it slides up and down. Assemble the fork leg with the new bushes and note any tight spots. If you find a tight spot, as I did with my new steel bushes, then one could carefully relieve the outside diameter of the bush on a lathe by a tiny amount at a time until the fork slides up and down smoothly, using some fork oil as lubrication. Your emery cloth could come in handy in this case. It helps if you end up with a polished surface on the OD of the steel bush to reduce friction and wear in the alloy, but only do this if there is a tight spot. How does that sound to you?
 

DogT

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Dave,
That sounds good to me, since I don't have any tight spots with the new lower bushings in either tube. It probably would not hurt anything if one of the bushes is a tight fit on the stanchion. I can almost easily slide the bushing on the stanchion without resorting to any hammer or drift forces, it is just not an easy fit.

Thanks,
Dave
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