N/C Forks

[jezza]

I'm in the process of rebuilding my forks - 1966. I want to have the legs cleaned but the lefthand threaded plugs don't want to come out. Can I leave them in, or should I remove them? Do they tend to be difficult item to remove? Any advice appreciated.

[Jordan]

Big top plugs or small drain plugs?
Usually possible to remove if destruction of the plug is an option.

[jezza]

They are at the bottom of the legs, the damper rods attach to them.

[Ventodue]

(Always helps to include a part number, Jezza - or even better, a parts diagram).

I guess you mean this one?

250 n-c fork.jpg

You sure it's left hand thread? There's nothing in the parts book or the workshop manual that suggests it is ...

[Bevel bob]

I seem to remember having to make up a tool to hold the damper from above to stop it rotating and this allowed me to undo the bottom fixing ? Normal thread.

[Ventodue]

I seem to remember having to make up a tool to hold the damper from above to stop it rotating and this allowed me to undo the bottom fixing ? Normal thread.

Yeah, I thought that's what the story was, Bob.

[Jordan]

"Rattle gun" type impact drivers (beloved of tyre fitters) are a good alternative for removing fork internals.
They usually work without needing some restraining tool.
I've owned one for about a year, wish I'd had it ages ago.
For removing stubborn parts, it's a much gentler tool than I thought.

[jezza]

Thanks all. It's part number 528 in your picture Ventodue. My workshop manual has the exact same diagram, and describes it as 'threaded plug - lefthand'. No part number though.

[Ventodue]

Ah ha! Now 'we're all on the same page', so to speak ...

(Part number is 0460.37.528, btw).

I'm out of my depth here, so hopefully someone can step in. I do note however that the instructions on rebuilding say "smear the thread with jointing compound". Assuming this was done originally, I can understand why it's now not easy to remove.

And also that its re-installation requires the use of a special tool - a "proper wrench", as it's described. Looking at the parts diagram and the illustration in the manual, it would seem that this "proper wrench" must have lugs that lock in to the cut-outs on the top of the "L.H. threaded plug" ...? Do you have such piece of equipment?

[Jon Pegler]

The special wrench Craig mentions is effectively a large screwdriver.
I've removed this part using an ex-army drag link socket, which is just a 1/2 inch drive socket with a large screwdriver end to it.
It is left hand thread and has a thin paper gasket sitting underneath.
I doubt the gaskets are available anywhere, but they are easily made with gasket paper.

Jon