which of 2 gasket types for lower fork screw plug?

[Major Softie]

Ken, your theory is completely correct on the Teflon tape and what it is best at, but that's not why I would avoid the Teflon tape. Little bits of it can get dropped down into the fork when you remove the plug and cause problems. That's why I would avoid it.

The teflon is for the large lower fork end cap that screws into the fork slider's bottom end and has a large copper 'gasket'.
I can't see how teflon would fall into the fork from the bottom.

Sorry, it LOOKED like a top cap, so I paid no attention to the fact that he clearly said it was a bottom cap.

I still don't like using teflon tape where pieces can get into fine orifice pathways, but, you're right, on the bottom would be far less likely to be a problem.

[chasbmw]

So what is the best way to seal the damper rod securing bolt on the bottom of these forks?

Copper omring inside and wavy washer on the outside?

[jjwithers]

Holy large signature image batman!

Yes, correct me if I am wrong but I simply did what the manual states - Copper ring inside and wavy washer on the outside. Nice and tight with a hex wrench through a ground down socket that i can tighten with a wrench.

[jjwithers]

I've had nothing but bad luck from Moto Bins.
Against my better judgement, I had to order something from them and while I was at it, i decided to order many more items to 'gang up' on shipping.
One of the added items is a fork rebuild kit.

The dang copper gasket for the lower forks is much to small to fit over the threads, or get threaded on.
Is it safe to re-use the old gaskets? Or should i bite the bullet and buy one for a better BMW dealer.

[Ken in Oklahoma]

The dang copper gasket for the lower forks is much to small to fit over the threads, or get threaded on.
Is it safe to re-use the old gaskets? Or should i bite the bullet and buy one for a better BMW dealer.

I would be inclined to re-use the old copper gasket. I would inspect it to make sure there weren't any deep scratches on it that might cause an oil weep. Then assured on that point I would anneal the copper gasket and give it a go, perhaps with a thin film of clear RTV wiped onto the surface.

And if that didn't work, then I would order in a new one.

I've also got a bit of an off the wall idea for stretching your new gasket. There is such a thing as an exhaust pipe expander intended to stretch the diameter of an exhaust pipe to slip over another piece of pipe. Such a tool could easily expand the new copper ring. Of course I would take the precaution of annealing the new ring first to make it easy to stretch and compliant to the surfaces that will compress it.

Oh, to anneal copper just get it red hot with something like a propane torch and let it cool. Unlike carbon steel the rate of cooling isn't a factor in the "hardness".

Caveat: This isn't something I've done. It's something I'm pretty sure will work.

Ken

[jjwithers]

My first thought was 'how can i expand it' and the pipe expander came to mind. I don't have a pipe expander, nor do I know anybody who does.
I'm so pissed at Moto-Bins (and myself for ordering from them again). I've had horrible experiences with their items. I wish I discovered this earlier but who test fits every single part when you order dozens of parts at one time?
They use many aftermarket items and you never know if you are getting a BMW part, or some knockoff.

[Zombie Master]

That copper gasket looks like a crush washer. Once crushed you shouldn't use it again. But if all the gasket surfaces are good it should work. I don't like jamming up fine threads threads with teflon tape. If all the parts are clean and straight I like to lightly grease them to get a good feel when tightening. You just want to get the washer crushed and not overtightened because it could get out of shape and leak....IMO

[sprints@pldi.net]

Out of curiosity - I noticed that no one mentioned using a conventional paper / fiber gasket and whether it did the job or not - Rod

[Major Softie]

Out of curiosity - I noticed that no one mentioned using a conventional paper / fiber gasket and whether it did the job or not - Rod

Large diameter, small surface area. Because of this, the crush washer would be preferred. I suspect a conventional gasket would seal poorly without some type of sealant, and then it has to be cleaned off each time. Still, it's a solution that doesn't involve searching for and waiting for the "correct" item.

[Duane Ausherman]

I haven't really seen the copper O rings leak, but it seems like they should leak more than those older stiff cardboard gaskets. That copper isn't a crush ring. Ever seen on crushed? Neither have I. They don't crush with the pressure that we can put on that plug. I have reused both types with no ill effects. In fact I can't recall using a new one of either type. Maybe I just don't recall.