Top Nut Loosens

Stevesplatto

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Hi,
I've got an '83 R80G/S that I've had a few months now.
just recently, started on the Welsh National Rally, the steering stem top nut keeps loosening off.
I'm tightening the nut to 80lbft.

Should I use loctite or does this point to another problem?

Thanks
s
 
Hi,
I've got an '83 R80G/S that I've had a few months now.
just recently, started on the Welsh National Rally, the steering stem top nut keeps loosening off.
I'm tightening the nut to 80lbft.

Should I use loctite or does this point to another problem?

Thanks
s

Same used to happen to my PD, Loctited. :thumb2
 
The nut loosening can be caused by the top plate flexing, and on my well used G/S was a sign the top plate was fatigued and near to failure. It was bent and twisted too.

I replaced it with a billet yoke from SJ BMW and the nut doesn't move with 60 ft/lbs.
 
The nut loosening can be caused by the top plate flexing, and on my well used G/S was a sign the top plate was fatigued and near to failure. It was bent and twisted too.

I replaced it with a billet yoke from SJ BMW and the nut doesn't move with 60 ft/lbs.

i've been looking at those. any distributors in the UK you know off?

Cheers s
 
No, but he often has them on Ebay and you can order direct from SJBMW on his web site.

They don't have a G/S specific set so the early 36 mm ones are what to order, and they will require a bit trimming as they are wider, to accommodate two more bar mount holes.
The indicator mounts are not a direct fit either, but if you flip them over to the opposite side they do and you would never notice the difference.

They are a big improvement on my old, flexing/ twisted set, as you would imagine, with an improvement in both handling and fork action.

And no more tightening that nut after every ride.
 
i've been looking at those. any distributors in the UK you know off?

Cheers s

Save your money they make no appreciable difference to the handling at all that I could see. I had a genuine San Jose one that I sold on after running it for a while. Your upper indicator mount doesn't work with them either so you will need to suss out a new indicator mount setup.

Have you got the washer in place that sits under the top nut? I've never had any issues with nuts coming undone with the steel top yolk so you have something amiss somewhere.
 
I worked on a PD where the nut kept coming loose no matter how many times I tightened it. I eventually worked out it should have the washer rob mentions, and it was fine thereafter.
 
Helpful tip - mark the adjuster and locknut so you know if anything is coming loose. Won't help cure anything, but gives a quick visiual indication of loosening. Did it on mine as in South America it kept coming loose aftre hammer on repio. Much quicker and easier than going round checking nuts etc for tightness.
 
Thanks for the responses.

As far as I know there is no washer under the nut. Checked the microfiches and manual.

Had another go it it yesterday. realised that the top yoke was powder coated by the previous owner. I think the nut was coming loose because the paint was compressing.
I've degreased the threads, scrapped away the paint, loosened up the pinch nuts and loosened and torqued down the nut a few times.
Meant to loctite it but I've put it somewhere really safe :-(.

I'll mark a line in line with the bars on the nut and see how it goes. (good tip thanks)

Really like the look of those toaster tan parts, seem to be more accommodating the the sjbmw ones.

I've also heard of a conversion whereby the bottom yoke is separated from the stem, lipped over and drilled out to a snug fit and new holes for the bars. Sounds feasible but ugly.

BMW always like to do things different which is what i like about them but that top yoke doesn't instil the most confidence I gotta say!

Once again thanks for the quality responses.

Steve
 
The problem with the Toaster Tan triples is buying one - I could never get a reply from him, and gave up in the end.

He doesn't always have G/S ones either, and his price plus postage is more than twice SJBMW.

As Rob has said , strength isn't a big factor, - on a good tight, well aligned set of road bike forks the stock plate is strong enough. I fitted a billet triple from Motobins to a 45,000km old R75/7 which had only seem road use, and like Rob found no noticeable difference.

But my G/S had done almost 300,000 Km, a lot of that fully loaded on dirt, and you could actually see the forks twist and flex, and the nut just wouldnt stay tight. When I removed the top plate it was bent , twisted and was fretting round the fork holes. Fork action was horrible, but handling wasn't too bad.

It was replaced with a SJBMW top triple and a Flatracer lower brace added. All that was required to make the indicator brackets work was to turn them upside down and fit them on the opposite side.
Assembly was simple , the billet top triple makes it much easier to align the forks if you are working single handed, and there is no need to tighten everything up to 90 odd foot pounds either.

The result, on this well worn bike , were excellent. The flex was gone, the top nut no longer unscrewed, the fork action improved ,probably due to the better alignment, and the handling improved a little, although not as much as I would have anticipated with the removal of all the flex.

And they look trick too.
 
With access to a milling machine a bottom yolk can be turned into quite a good top yolk that looks acceptable for very little money!
 


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