Author Topic: Front fork bushes  (Read 621 times)

Offline ShaunMac

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Front fork bushes
« on: 03.07. 2014 16:46 »
Help please?

Just rebuilding the front forks after re spray. Got new bushes but they're a little tight. The lower bush goes in as far as the top oil hole but then tightens up. The bush is scoring so I'm presuming from internal scratches. Unfortunately my honing tools too big for it.
Am I safe to run some wet & dry on the bush?
How tight is too tight?

Thanks,
Shaun
61 Super Rocket swing-arm

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Re: Front fork bushes
« Reply #1 on: 03.07. 2014 20:41 »
Hi Shaun - just happen to be rebuilding my forks during a respray so took a pic or three
The bottom fork should only go on as far as can be seen in the pic so you can compare how yours are.

to assemble the fork you need to slide the following up the Stanchion in order -The fork seal holder (with seal) - circlip - shim - top bush - then the  bottom bush goes on as far as can be seen in the pic then is held on by the big nut that screws into the stanchion.

Shim is the nasty bit as if its too thick or thin means sliding every thing off again, some people advocate cutting the shim to make fitting it easier, never done this but probably can be done without issue.
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline ShaunMac

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Re: Front fork bushes
« Reply #2 on: 03.07. 2014 20:49 »
Hi Bill,

Built it up like that, the problem is sliding it back in the housing. It's tight and scoring the new bottom bush.
Am I safe just running some emery around the bush? That's the only way I can see of getting it in.

Cheers,
Shaun
61 Super Rocket swing-arm

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Re: Front fork bushes
« Reply #3 on: 03.07. 2014 21:12 »
Ah right I see
OK first thing I do would be to try the old bush in again ( why you ask ) I had a similar problem with my last project, what had happened was the fork leg (slider) had distorted while removing the old seal holder, was barley measurable but gave the same symptoms you have, if the old bush goes in ok then it probably is the new bush that's wrong, if the old bush is tight as well then the tube is distorted.
If the tube is distorted then what I did was to use the old bush with fine grinding paste then sovol autosol to hone down the high spot on the tube  then the old bush can be discarded after, needles to say this requires copious rinsing out afterwards.
Using emery cloth on the new bush mmmmm, possibility of fine particles being left in the bush, more so than in the steel of the tube, I'd be inclined to send the bushes back if possible or find someone with a lathe and skill
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline ShaunMac

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Re: Front fork bushes
« Reply #4 on: 03.07. 2014 21:21 »
Thanks Bill...was thinking of a way to get a bit of grinding paste down and never thought of the old bush.
That'll keep me out of mischief tomorrow.

Cheers,Shaun
61 Super Rocket swing-arm

Offline ShaunMac

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Re: Front fork bushes
« Reply #5 on: 04.07. 2014 11:41 »
Worked a treat that Bill.
Used the old bush with some fine paste and I could see a flat spot. Worked at it then out the new bush in and lapped that one in with a little bit of paste and the auto sol.
Gave it all a good clean up before assembly and now it's smooth as.....
Cheers,
Shaun
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Re: Front fork bushes
« Reply #6 on: 04.07. 2014 13:44 »
Well done
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco