GT750J fork tube pitting corrosion (fixes to slide seals on?

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GT750J fork tube pitting corrosion (fixes to slide seals on?

Post by Olafskii »

Does anybody have any suggestions for fixing the pitting corrosion on the fork tubes to allow sliding the new seals on?

My GT750J forks are corroded immediately above the triple tree clamping points. These are the original fork tubes. You can see from the photos that the factory chrome ended just below the lower triple tree clamps. Is there a risk that this pitting will damage the new seal when it is slid into place? (I'm not too worried about compromised mechanical strength because the area above the clamp is a low stress part of the fork tubes.) If there's a risk of damaging the new seal, does anyone have a recommended fix?

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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by rngdng »

Install the seals in the lower legs, and then install the upper tubes. The seal will never come in contact with that area at all.

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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by TonupKid52 »

Hi You can use a plastic bag or other thin plastic sheet. put the plastic in a cone shape at top off leg push seal on this and down tube
to where you need it. iv'e done this and it works well no damage
hope this helps
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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by akendall1966 »

Wrap it in cling film / Saran wrap oil it and they'll slide over in harmed
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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by Suzukidave »

To make that pitted area look a bit better i wonder if some JB weld smoothed over that area and sanded smooth would hold ?
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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by jabcb »

+1 on using plastic. That’s what All Balls recommends. ... isassembly/
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Re: GT750J fork tube pitting corrosion (fixes to slide seals

Post by Suzsmokeyallan »

Buy some RC modellers Zap-a-gap super glue, you will want the gap filling type, and glue up any pits you find. Deeper pits will take a few applications to address, then lightly sand the tubes to blend back down those spots you filled in. Its better a seal go over a filled spot than to drag through a pit which causes leaking and micro tearing of the seals lip.
You really want to put the stanchions into a lathe or have a way to spin it to put back the factory ground appearance back on the hard chrome. On old bikes the hard chrome often gets weathered /smoothened over from years of use.
As always don't ever sand lengthways up and down the stanchion tube, always sand in a direction around the tube.
I've put some stanchions that were physically abused by previous owners in my lathe and found paper like 400, 600 or even finer grades soaked with WD40 brought the factory hard chrome ground finish back to the stanchions. You don't need it to spin fast, approximately 100 rpms is enough, you just want to be able to go ever so slowly up and down the tube as its rotating, recreating a surface like the oem ones that will help keep the seals doing their job.
Always start with the finer grades like 1000 and work back towards the coarser grades of 400 if you find the one you are using is not coarse enough.
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