How To Repair The Steering Head On My Motorcycle?

As someone who has been riding/repairing/rebuilding motorcycles pretty much all my life, and has frequently encountered this "problem", here is my solution. Use a retaining grade of Loctite, up here it would be 609, or something like that. Clean the bores in the frame very, very carefully. Then clean them again. Get a long piece of threaded rod, studding, whatever they call steel rod with thread all over, in your neck of the woods, some suitable nuts, and some big washers that are bigger than the o/dia of the races. Length of the studding should be 50mm or so longer than the length of the headstock. Then clean the steering head stem again, and clean the bearing outer races. Apply the Loctite EXACTLY i.a.w. instructions. Assemble the race outers in the headstock, and clamp in place with the studding, washers and nuts.
As long as you stick to the instructions this works every time. Personally the thought of centre popping to provide a press fit leaves me rather cool, especially for a classic like your BMW!
best of luck
cheers
Bill
 
I am surprised the race cup was not made to be replaced. All the motorcycles I have worked on the race cup can be tapped out and replaced. Maybe I have been lucky that way. But I would just use a bearing retaining compound as I know they hold fantastic. I have used the retaining compounds in work and know how well they hold.
 
I am surprised the race cup was not made to be replaced. All the motorcycles I have worked on the race cup can be tapped out and replaced. Maybe I have been lucky that way. But I would just use a bearing retaining compound as I know they hold fantastic. I have used the retaining compounds in work and know how well they hold.

I believe he's saying it's the outer race cup that is a loose fit in the frame boss. I would be questioning how that boss got loose as the most important item...looking for micro cracks, etc. Perhaps the new? race he is using is not correctly sized?? If no cracks/fatigue on the frame, then locktite , JBweld or some such epoxy based formula would do the job. If it's a "good" fit, just not a press fit, locktite is the way to go. The limitations of those products is high temp related, and therefore of no concern here.
 
From the photo it looks like it is the outer race that is loose in the neck cup. The neck cup that holds the outer race is replaceable. That was what I saw. Guess I missed something.
 
I believe the head stem is a forging (going by the looks of my own R26). So you should be able to put a bit of heat in it - but not enough to heat up the oval tubes which are some kind of chrome-moly. The cup boss is almost certainly tapered from multiple bearing replacements, rather than 'rolling' wear. I would heat up the very top edge only and only just dark red at most. Then using a heavy hammer but with little force tap all the way around the top edge - checking the reduction of taper as I'm going around. once the bore is close to cylindrical again, I'd put the bearing cup in (preferably an old one or an old ball race the same OD) and then tap on any loose spots until it fits as close a perfectly as you can get it. So you are kind of reforging the boss. The cool it down, clean thouroghly as described by others.
Lastly Loktite the cup in. Should last another 50 years.... :)
 
Mal,
you heat the area where the bearing light red and spray with water . That will shrink that area . don't get it any hotter than you have to do the job. you should be able to pull the races in without too much trouble. make a ring to fit around the the head where the bearing sits . That should do it.
 
Thanks everyone for your input - while I have not actually undertaken the repair yet - delays have been caused by other priorities. I am back in the saddle. My first attempt will be to make a tool for the press as outlined by Tony and put it in the press and see if I can effectively reduce the inside diameter to a better fit. As far as a reinforcing ring goes - I think I will try this on my second frame where my ambition is to customise the bike as an R69GS - scrambler with knobby tyres and high exhaust etc - sort a modern version of the old ISDT BMW's from the 1960's.

Mal
 
Juice,
The boss that the outer race goes into is replaceable on many necks. It may look like it is part of the neck but sometimes is replaceable. I have replace them on Honda's, Triumph's and Harley's. That is why I say to look closely as it can be hard to tell unless you look at the inside of the neck also. I have replaced those cups many times through the years. If they are not replaceable I would prick punch the neck to make the race tight and also use retaining compound.
 
I personally, and it's just my opinion, that punching the ID is not the best way to permanently repair this thing. Whatever stretched that ID would soon push down the area around the punch marks. Compare the surface area between the small upsets and an entire ID of contact. If I was out on the road that would be one thing, but Mal is in a shop where he doesn't have to compromise. And yes, I am considering that the area between those punches could be filled with a chemical. Again, to me it's a compromise. But that just me. Mal is free to do as he pleases, just as we all are.:)

I do entirely agree though, that if they were replaceable, that would certainly be the easiest, safest repair. My thoughts have been limited to a non-replaceable part.
 
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