Thrust Bearing

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Hi,
I have noticed a rumbling/rattley noise on the bike that disappears when I pull the clutch lever in (i.e. it touches the handlebars). It doesn't seem to matter if the engine is hot or cold and I can hear it without earplugs on the move. I've looked through some posts here and think that it may be the thrust bearing in the clutch.

Could someone give me a method of diagnosis for the thrust bearing? If it is the thrust bearing, could someone point me in the direction of some instructions on how to replace it? Haynes seems a bit vague on this!

Thanks,
DA
 
Hi,
I have noticed a rumbling/rattley noise on the bike that disappears when I pull the clutch lever in (i.e. it touches the handlebars). It doesn't seem to matter if the engine is hot or cold and I can hear it without earplugs on the move. I've looked through some posts here and think that it may be the thrust bearing in the clutch.

Could someone give me a method of diagnosis for the thrust bearing? If it is the thrust bearing, could someone point me in the direction of some instructions on how to replace it? Haynes seems a bit vague on this!

Thanks,
DA

And I should have mentioned the bike is a '94 1100GS, with 73,000 km on the clock (not sure what that is in miles).
Thanks,
DA
 
Oh dear...

I hate to be the bearer of bad news, but that sounds exactly like the kind of noises mine used to make. Mine's a '95 model, yours is '94, so likely to be the same gearbox. And that's where my trouble lay. They have a tapered roller bearing at each end of the input shaft. When I took mine apart, the one at the rear of the shaft was shot. That's the bad news.

The good news, there's two bits of that, sort of. First, mine started making these silly noises in March 2001. I continued riding until October 2007, covering 50k+ miles, before finally stripping the box. It made the noises throughout, but I never had any other trouble, save for nice shiny metal flake bits in the oil when changed.

Second, I didn't find the repair too difficult. A mod was made on later boxes, ('97+ ?), where the tapered rollers were replaced with sealed ball bearings, and BMW recommend this mod, apparently. Me being a contrary git, I decided that the original set up was the better option, considering the application, so I replaced mine with new tapered rollers.

Unfortunately, having done this last summer, I haven't yet been able to test the re-built box on the road, as another problem (Injectors wouldn't fire) turned up after I'd re-built the bike. That was August, I think; I got pissed off with t ebike, and haven't touched it since.

There are several threads on here about re-building gearboxes, one in particular by a guy down in Lincolnshire, but I can't remember his handle. haven't been on here since September-ish. Hang on, I'll have a look through my old PMs and get back to you...

Dave.

Back. Kompost is the guy's name, have a look for his posts. Though he did a different mod on the later gearboxes, it will give you some idea of what is involved.

It may also be wise to see what, if anything, Steptoe has to say about your noises; he's The Man for all things GS on here, but the above relates to my experience...
 
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Rattling that disappears when you pull the clutch lever in is not unusual on M93 boxes - i.e. the original ones. This in itself doesn't warrant any corrective action; it's when you get bits of silver metal in the gearbox oil that you need to do something about it - as has been said, that's the taper roller bearing breaking up. Copper coloured metal bits is the selector forks waving bye bye and usually follows the infamous skipping in third or second gear.

I would check the oil before ripping it to bits. Scriminger Engineering is the place for gearbox rebuilds.

Regards
 
Thanks so far

Hi,
Thanks for the bad news! Being a pessimist I assumed that it may be a gearbox off job, but Steptoe mentioned replacing a bearing that might do the trick and I wouldn't have to take it all to pieces.

Can anyone shed any light on which bearing and how to replace it?

I can just imagine the dealer's eyes lighting up if I take it in for a quote...
 
Sounds very familiar. Mine was the same for the last few thousand miles. Eventually the clutch cable went slack. The bearing and clutch pushrod were both knackered. While it was being done I had a new clutch fitted as well - bike is coming up to 50,000 miles (about 80,000km), and the clutch plate was very nearly worn out. Given the mileage yours has done your clutch might be tired as well. Maybe not if you do loads of open road miles (I do loads of town miles commuting across London) but it's worth thinking about if you're contemplating clutch work to do it all in one go.
 
As Trullion says, first ting to do is check the oil. I had a lot of 'metal flake' effect in mine, and on the magnetic plug, some of the bits were up to 2mm wide, and around 5mm long. Sounds serious, and it looked serious, but as I said, it did fifty thousand plus miles before I decided to strip it. I made that decision because for a couple of months a new silly noise had made itself apparent; a sort of 'groaning' sound, just as the clutch engaged.

One thing I discovered when I had the box off, was longitudinal play i.e. a lot of end float, about 2mm, on the input shaft. As tapered roller bearings work on a slight pre-load, there shouldn't be any end float. Not sure just how you'd check this wit the gearbox in situ. It would mean a swing arm off job, and remove the clutch activator, thrust bearing and actuation rod. You'd then need something to grip the end of the input shaft, possibly internally in the actuator rod tunnel, and try pulling/pushing. Any movement would not be the best news you could hope for.

I didn't find it too difficult to replace the bearings (by the way, one each end, it could be either; it was the rear one on mine*, but I replaced both), but I did need the help of a mate to remove the inner cone from the shaft, and the help/advice of Steptoe for removal of one of the outer cones (front, I think) which sits in a blind housing.

It's nearly a year since I did mine, but I'll try to remember what I can, including the fact that I still owe my mate a bottle of Wood's 100 for his help...:D

Dave.

* Just had a look at an input shaft. They have a helical gear at the rear end. The rotation of the shaft would tend to put pressure on the shaft towards the rear. If a bit of play developed, this would become a slight 'hammer' action on the bearing surfaces when the clutch is engaged, especially if you're a bit sharp with it. Do you have a slight 'clunk' just as the clutch engages? I seem to recall I had. So, as for which one is knackered, I'd say the rear. But the front one will have been running loose as well, so replace both. I got mine from a bearing factors, cost about twenty-two quid for the pair.

Another edit: You say Steptoe mentioned a bearing that can be replaced without removing te box. The only one I can think of is the 'thrust' bearing behind the clutch actuator arm. I'd ask Steptoe if he could clarify which one, and do that before you take any notice of what I've said, his knowledge of GS's is many orders of magnitude above mine...
 
Dude, i have a 94 1100gs, 52000 miles, and it makes the same noise,the noise is not mechanically painful ( grinding,banging etc) it is constant and therefore nowt for me to worry about, if i hear any change in volume or harsahness i'll think about a re-build.

Try not to loose sleep over your bike m8, the early boxes are pretty agricultural in build and do carry a degree of running chatter.
 
Dude, i have a 94 1100gs, 52000 miles, and it makes the same noise,the noise is not mechanically painful ( grinding,banging etc) it is constant and therefore nowt for me to worry about, if i hear any change in volume or harsahness i'll think about a re-build.

Try not to loose sleep over your bike m8, the early boxes are pretty agricultural in build and do carry a degree of running chatter.

i DA,

I I think Mac has summed it up pretty well, that's what I did, it was only when I got a new noise that I did something.
Dave.
 
So the summary is:

All gearboxes make some noise. Some of those noises are worth worrying about as damage is imminent, other noises are not really that important as damage will be impending, but probably not for a while and other noises are perfectly natural and 'They all do that sir'. :drool

If my noise is one of the first type I should worry and take the gearbox apart before it all seizes and my bike turns into a twisted lump of metal. If my noise is one of the second type I can wait until another noise starts, in which case that is probably one of the first type and I need to break out the spanners and the latex gloves. The third type happen all the time and are part of the joys of owning a bike that was designed on the back of an envelope in 1928 and can be fixed with a hammer.

Does anyone produce a CD of all the different noises, so that people like me can diagnose faults?

I think I may break out the latex gloves anyway. Just in case, you understand... :augie
 
I DA,
Hmmm... I've thought about what I said above since I said it, and there is one or two points I think I should add.

Yes, mine did a further fifty thousand plus miles after the noises started. But I was always aware that, if an engine seizes, if you're quick enough you can always pull the clutch in and coast to a stop. If a gearbox seizes, pulling the clutch in does bugger all, and you're likely buggered.

Being aware of that, if I'd had the money to get a dealer to do it, or the confidence in my own spannering ability, mine wouild have been done much earlier.

As an upside-downer (as we call one Aussie on another forum :D) you've got youe winter coming on. Maybe it is a good time to break out the latex gloves...

Dave.
 
Hi Dave,

Thanks for all the advice - this really is a superb forum for help. You're right, the nights are drawing in down here and not only that, I have the end of term in sight so I could spend a couple of weeks doing this in a steady fashion.
Any chance you (or someone else) could list the parts that I would need so I can give Motorworks a ring. They're practically on speed dial :(

By the way, I noticed you're in Kendal. I'm from the Lakes as well, my folks still live over on the western side. A beautiful place.
Cheers,
DA
 
Hi again,

I didn't get my bearings from Motorworks, I got them here:

http://www.eriks.co.uk/branchfinder/branch.asp?centreid=65&branch=Lancaster Service Centre

The dimensions are: Front, 50mm x 25mm x 15mm, Rear: 50mm x 20mm x 15mm.

Apparently they are a 'standard' size, so shouldn't be a problem getting them over there, though Eriks do do a mail order service. The sizes are the same for Tapered Roller or Ball Bearings. You want the sealed Ball Bearings if you go down that route. You could probably get those from Motorworks, though they will cost about twice the price... :(

The other things it would be wise to get (Motorworks) are a new set of oil seals, you can find the details for those on the R1100GC 'Exploded Parts Diagram' near the top of the first page.

Make a note of the sizes of the shims that pack the bearings, and keep them in seperate bags. If you replace with tapered rollers, in theory these should set the pre-load for the new ones; in practice that didn't happen; they were to tight, and I had to do some fiddling. You'll probably need to do some 'shim shuffling' to get the correct end float for Ball Bearings.

A heat gun is needed to remove the gearbox lid; although the tapered roller on the input shaft just comes apart, the intermediate and output shafts both have Ball Bearings; you need to heat the bearing housings before persuading the lid off with a soft faced mallet.

One of my outer cones came out easily, one didn't, and needed the attentions of a mate with a Mig welder. Steptoe is probably the best foradvice on that one, I aintgot a clue how he did it. A method of removing the inner cones from the shaft is also needed. A puller is a good idea; though my mate did it with an angle grinder, I wouldn't recommend this...

I'll try to think back twelve moths or so to anything else I can remember. And don't forget that thread mentioned earlier from the guy in Lincoln (forgettn his name again :blast

Cheers,

Dave.

P.S. Yep, The Lakes is the best corner of England. Except perhaps the Yorkshire Dales. Or maybe Cornwall.
 
Just back from a run trying to avoid the showers arounf Aberdeenshire and for once shut the bike down outside of the garage, sorted out the kit , took out the ear plugs, and then fired the engine back to help me get it into the garage as its a bit up hill :comfort That's when I noticed a rumbling sort of noise that went when the clutch lever was pulled in. Does it when on the centre stand as well and is irrespective of a gear being selected or not, so have I:

1) Committed the BM original sin of running the bike without ear plugs in, as if you do you'll hear all sorts of nasty noises / rattles / ticking etc etc?
2) A clutch problem that needs sorting out before I go down to the south of France early next month?
3) A problem that will last xxxx thousands of miles and will only need fixing when my ear plugs need replacing?

Bikes a '98 R1100GS with about 25 000 miles on it. TVMIA :thumb2
 


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