Clutch replacement question...

[Willie]

Need to replace the clutch disk in a 1150RT. I was told that I need to install a whole new clutch pack instead of just the disk and new bolts or it will slip in a few thousand miles. I've never heard this before. Any reason I can't just put in a new disk?

[Tony_K]

Drink the Kool-Aid already!

[awagnon]

I just replaced the clutch plate and the non-reusable clutch housing bolts on my 2002 1150RT two years and 30,000 miles ago and it works perfectly fine.

[Tony_K]

I just replaced the clutch plate and the non-reusable clutch housing bolts on my 2002 1150RT two years and 30,000 miles ago and it works perfectly fine.

 

Yup, Same here 4 years ago... with all good used components! Disc, pressure plate and same "worn" bolts. 50k+ since still rolling rolling rolling...

 

 

 

 

[Boffin]

I would not risk the used bolts - they are stretch-to-fit and you run a high risk of having one or more shear in use or of them coming loose due to insufficient clamping pressure.

Fitting just the friction plate is fine, providing the pressure plates are flat and not scored. That said, it is a lot of work getting in there to change it - a long-day's work - so you need to factor that in as well.

 

Andy

[Peter Parts]

Why has it gone bad? If not due to a fluid leak or over 200,000 miles, you first need to replace the rider.

 

If it is a lot of effort and cost at the dealer, sure, replace all the pieces while it is open. Otherwise, use your judgment. But it sounds to me like the usual CYA BMW recommendation to replace everything in sight when only the disk is gone - although Boffin may be right about the bolts, if you want to be careful.

 

BTW, think about replacing seals and other stuff in there; and if you have a hydraulic clutch, doing the drain trick. Do the Oilheads have throw-out bearings on the clutch rod?

 

Ben

[dan cata]

If I would be you, I would take it off and if the metals have seriosu burning dots and cracks, I would change them too.

 

Last time I did it on the GS, only replaced the 6 bolts and the friction plate. Next time I will only replace the friction material as the hub splines were in top shape

 

Dan.

[Willie]

Low miles and everything is minty, BUT the splines are shot. Tranny is off to be rebuilt. I actually have access to a low mile used friction disk. Is that worth saving $150 or so? I'll just buck up the cash for the new bolts though.

[Willie]

Drink the Kool-Aid already!

 

What??? I already drank a bunch. Why do you think I ride an RT

[AndyS]

Hi Willie, what mileage do you have on that bike?

It is worrying to read of the input splines gone Kaputt, as it will probably do it again.

Others on this forum have also talked of checking the rear main bearing for wear, but my concern is a misalignment issue on your gearbox.

[dirtrider]

Morning Willie

 

You shouldn’t have to replace anything except the disk & the bolts. You really didn’t fail your clutch, all that failed was the clutch hub and input shaft.

 

Some of that replace everything mantra is a carryover from the 1100RT days where the clutch parts were changed about 1998 and BMW didn’t supply the early clutch parts anymore so when a new (later) disk was installed it needed the later cover/housing to go with that disk.

 

As mentioned above you really need to find out why those input shaft splines failed. If you don’t it will fail again in about the same mileage range.

 

In my opinion the usual reason the clutch splines fail is a misalignment between the trans front housing and rear of engine (input shaft doesn’t align with center of crankshaft) but there is speculation by some that it could be a loose rear main bearing. Personally I don’t buy into the rear main being the cause as I have seen some 1100’s with extreme rear main bearing wear and no failed input shaft splines. I also repaired a friends 2002 1150’s that had the clutch splines stripped and the rear main was good as new but the trans was not centered on the crankshaft. I used the front trans housing as a measuring fixture using the front bearing center as a datum. I then machined up off-set alignment bushings to center the trans front housing on the engine. That was at around 23,000 miles and he now a bit over 89,000 miles on the bike and it’s still going strong.

 

[Linz]

D.R. If you remove the starter on an R1150RT, can you see (albeit with some difficulty) whether you have spline issues or not?

 

If so, what would I be looking for? Rust? Bright worn surfaces?

 

I'm not keen to break her back on a whim just to check. 2002 R1150RT, 37,000 Kilometers (23,000 miles). No typical indications of issues as yet.

 

Cheers,

 

Linz

[OoPEZoO]

D.R. If you remove the starter on an R1150RT, can you see (albeit with some difficulty) whether you have spline issues or not?

 

If so, what would I be looking for? Rust? Bright worn surfaces?

 

I'm not keen to break her back on a whim just to check. 2002 R1150RT, 37,000 Kilometers (23,000 miles). No typical indications of issues as yet.

 

Cheers,

 

Linz

 

Yes, to an extent. We did this with Willie's bike a few weeks ago to check things out. If you have clutch spline wear, you can most definitely see that there is a problem by removing the starter. There should be no rotational play between a transmission input shaft and the clutch disk hub. I verified this when I rebuilt me transmission 2 years ago. When everything is new it slides together easily, but you should not be able to rock the clutch disk back and forth on the shaft due to the splines fitting snugly into the cltuch hub. On Willie's bike, we removed the starter, put the bike in gear, and rocked the rear wheel back and forth. You could plainly see that there was rotational play between the input shaft and clutch disk. Meaning, you could rock the rear wheel and see the input shaft move back and forth without the clutch disc spinning. Dead ringer for spline wear.

 

Last night I helped him remove the transmission and we confirmed that his splines were on the way out. His splines didn't look terrible (maybe still about 50-60% left), but there was certainly some unusual wear. His clutch disc on the other hand looked like it was VERY close to letting loose. Obviously, once this happened it would have destroyed the input splines completely.

[dirtrider]

Morning Linz

 

 

Yes, at least a pretty good guess as to extreme clutch spline wear.

 

I don’t have total confidence in spline condition gauging by looking in through the starter opening but it’s better than doing nothing.

 

You can kind of prove a real bad wear issue but very difficult to prove conclusively a good one.

 

Some have removed the starter then pulled the clutch lever in & tie strapped it there then used a pointed bent wire or a pick to move the clutch disk on the input shaft.

 

Personally I’m not real impressed with doing it that way as that allows the clutch disk to drop down on the input splines and engage better so even worn ones can show better than they really are.

 

The way I do it-- (not that it’s the best way it’s just the way I feel the most comfortable with)—is to ride the bike until warm, then ride it slowly while plying with the clutch lever to disengage then re-engage the clutch a few times to try and get the disk centered on the trans input shaft. From then on I do not dis-engage the clutch even when I get back to the shop. I just coast in then kick the trans into neutral. Hopefully that leaves the disk centered on the input shaft. Then remove the starter & use a bright light bulb on wire to go down in & light the inside of the clutch housing. Then with trans in gear I move the rear wheel to turn the input shaft as I watch it move inside the clutch hub.

At this point you can pull the clutch lever in & hold it there if you want to try the “rotate the disk on the shaft way”.

 

 

 

[Linz]

Excellent and detailed answers from you both. Thanks, I can do that easily and I'll check it at the next service.

 

I appreciate the help.

 

Cheers,

 

Linz

[Willie]

Met up with the guy who is doing the trans. Very well known for doing this stuff. He still said that I should do the whole clutch assembly for fear it will start slipping in 5-10k. At this point, I'm not willing to put anymore money into this. He insists too that the alignment problems are inside the trans with a worn or misinstalled front or rear bearing. I'll hold him to his word about never getting a trans back. I hope he's as good as everyone says. I'll let you guess who it is as I don't want this to sound like a smear campaign on a guy with a good rep. I'm just doing the disk and bolts and hoping that there is no problems with alignment in the future. Honestly, it will be years before I would know as I tend to use my KLR more for daily riding and the RT is for the limited trips and long rides that I seem to never have a chance to take. Hope that changes now that my daughter is off to college this Aug.

[dirtrider]

Afternoon Willie

 

I don’t know, something doesn’t compute correctly on this. Must be more to his statement than that.

 

The spline problem I repaired for my friend had a mis-alignment of the front trans housing to the engine & the trans input shaft bearings were tight & like new. The internal bearing alignment is the alignment you get as the trans bearing bores are fixed in the cases & shaft is centered in those bearings.

 

Will he guarantee the trans won’t tear those splines out again by standing behind it until you sell the bike? Somehow I don’t think he will.

 

 

As far as not getting any back, that part I believe —Who would send a 2nd trans failure out to be repaired at the same place again? Even the worst ones usually go over 20,000 miles so when they strip again the owner looks for another trans, or fixes it himself, or is on the road somewhere & gets it-repaired at a dealer on the road somewhere.

 

[OoPEZoO]

Afternoon Willie

 

I don’t know, something doesn’t compute correctly on this. Must be more to his statement than that.

 

The spline problem I repaired for my friend had a mis-alignment of the front trans housing to the engine & the trans input shaft bearings were tight & like new. The internal bearing alignment is the alignment you get as the trans bearing bores are fixed in the cases & shaft is centered in those bearings.

 

Will he guarantee the trans won’t tear those splines out again by standing behind it until you sell the bike? Somehow I don’t think he will.

 

 

As far as not getting any back, that part I believe —Who would send a 2nd trans failure out to be repaired at the same place again? Even the worst ones usually go over 20,000 miles so when they strip again the owner looks for another trans, or fixes it himself, or is on the road somewhere & gets it-repaired at a dealer on the road somewhere.

 

This is the same discussion we had in Willie's garage after we pulled the tranny and he was beating his head against the wall about what to do. I want to trust an "expert", but I'll be honest in that his explanation makes no sense to me. That input shaft has two huge sealed bearings on it front and back. They hold that shaft dead center on where ever the machined recesses in the case make them center it. One or both of those bearings wearing out could cause spline wear due to rotational slop, but at 30k miles his shouldn't be worn. Replacing them is going to put the shaft back in the exact same position. The only thing that could change would be the preload shims on the end of the shaft, but that has nothing to do with rotational slop.

 

So here is to taking a leap of faith......even if it defies common sense

 

 

[Peter Parts]

Maybe this is what the expert said:

 

some believable instances where the engine and tranny cases were found to be misaligned and hence the shafts aren't concentric. That leads to bad wear.

 

 

Even for an old machinist with a dial test indicator, very tricky to diagnose this condition. And the fix is horrible, as you might imagine.

 

About bearings not being quite square in their holes... dunno about that, as previous posters have said.

 

Frankly, I believe BMW clutches are almost forever, unless you have some bad habits from wet clutches beforehand... or the rare factory goof.

 

Ben

on the road from Toronto tomorrow... Hockley Valley Road, Black Birch Resto.

[awagnon]

Willie. Some, like Anton L., believe if you have a spline failure and don't have the ability to measure for axial misalignment, then you should change the entire clutch assembly including the clutch housing, pressure plate, etc. This is based on the possibility of the clutch having a runout misalignment that might be corrected by replacing everything south of the engine crankshaft. I don't know what data, if any, is available to support this recommendation.

 

When my splines failed at 43,000 miles I replaced the clutch friction plate (and six bolts), the input shaft, main front input shaft bearing (as it is sometimes damaged in removing the old one from the stripped input shaft), and ALL tranny seals. Since then I've put 27,000 miles on the bike and there is just a hint of wear on the new input shaft and clutch splines. However, I've been taking it apart every winter and inspecting the splines and re-lubricating them with the idea of another "preventive replacement" if they look bad before they fail on the road. So far the splines are still looking good. I did not measure for misalignment nor did I replace the entire clutch assembly. Fingers crossed...

[OoPEZoO]

Maybe this is what the expert said:

 

some believable instances where the engine and tranny cases were found to be misaligned and hence the shafts aren't concentric. That leads to bad wear.

 

Nah.....he pissed on the whole misalignment thing all together saying that he has never seen it on any bikes in his shop (so therefor it doesn't exist), and swears that the problem has to do with the bearings, setup, and shimming inside of the transmission.

 

Beats me. If I knew the answer, I would be riding my RT right now instead of parting it out

[awagnon]

Maybe this is what the expert said:

 

some believable instances where the engine and tranny cases were found to be misaligned and hence the shafts aren't concentric. That leads to bad wear.

 

I actually had a BMW dealer tell me that he considers the splines to be a normal "wear item" like the clutch or brake pads and therefore shouldn't be covered by warranty.

[jm1515]

... Some, like Anton L., believe if you have a spline failure and don't have the ability to measure for axial misalignment, then you should change the entire clutch assembly including the clutch housing, pressure plate, etc. This is based on the possibility of the clutch having a runout misalignment that might be corrected by replacing everything south of the engine crankshaft. I don't know what data, if any, is available to support this recommendation.

....Fingers crossed...

This is what I did when my Roadsta ate it's splines ~1000miles ago. Tranny re-built by RCRG and I replaced everything south of the engine rear seal.

My fingers are also crossed...but I'll be pulling it apart to check things every 2 seasons, now that I know how easy it is...

[Peter Parts]

Do the Oilheads have throw-out bearings on the clutch rod? Any need to replace or service them when the clutch is apart? Or how is that function handled?

 

Any mod to get a felt into an older, non-felt grooved, rod?

 

Thanks.

Ben

[awagnon]

Do the Oilheads have throw-out bearings on the clutch rod? Any need to replace or service them when the clutch is apart? Or how is that function handled?

 

The 1150XX bikes have a hydraulic throw-out bearing and it's mechanical on the 1100XX bikes. I did change my throw-out bearing and cylinder (it's all one piece) when I did my splines. Also, you might consider drilling an 1/8 hole in the bottom of the throw-out bearing cylinder cavity on the back of the transmission so any hydraulic leak will come out there instead of tracking north and fouling the clutch friction plate.

[Peter Parts]

Do the Oilheads have throw-out bearings on the clutch rod? Any need to replace or service them when the clutch is apart? Or how is that function handled?

 

"a hydraulic throw-out bearing"

 

Thanks for reply.

 

Ummm.... could you explain that further, please. Is there a thrust ball-bearing INSIDE the hydraulic cylinder enclosure or does it just spin the cylinder innards? Nothing obvious to me from the parts sheets and, thank goodness, never had one apart.

 

Yes, I've been tempted to drill the leak drain hole mod but not sure if I'll screw-up while trying to head-off a failure which is not common or should just give it a try?

 

Ben

[dirtrider]

 

No need to drill any holes just cut a 3/16” wide strip out of the bottom section of the mounting gasket, leaves just enough of a trough to allow fluid to drip out but not enough gap to allow dirt & water in.

[Willie]

Glad it was brought up about the drain for the clutch cylinder. Mine was damp with fluid so I'll do the cut on the bottom of the gasket and I'm going to order a new felt.

[Willie]

This guy didn't say anything about the housing, but said that he ALWAYS replaces the diaphragm spring, friction disk, and inner and outer covers. That will add a few more hundred, but the main clutch housing is the big dollar item in teh whole setup. I'll have $900 in an all new clutch assembly as opposed to "just" $180 for new bolts and a clutch disk. IF I knew that was an end all to the input shaft wear, it would be a different story, but it's still a crap shoot either way.

[Peter Parts]

No need to drill any holes just cut a 3/16” wide strip out of the bottom section of the mounting gasket, leaves just enough of a trough to allow fluid to drip out but not enough gap to allow dirt & water in.

 

Thanks for good tip about gasket - I suppose that would be a big enough leak-gap. While that is less potentially dangerous than drilling holes, not sure it isn't a semi-major task on my R1100S to get to the gasket, involving removing various uncooperative pieces?

 

About that nice arrow... what is it pointing to, please? Ball-bearing thrust bearing or what? Any maintenance needed for the throw-out bearing mechanism?

 

Ben

[awagnon]

About that nice arrow... what is it pointing to, please? Ball-bearing thrust bearing or what? Any maintenance needed for the throw-out bearing mechanism?

 

The arrow points to the actual thrust bearing which is part of the inner piston that slides in the throw-out cylinder. It has a spring inside so you have to compress it somewhat when you install it. No maintenance needed until it fails, although some people put a dab a moly grease or similar inside the bearing cup when they install it. I did.

 

I cut the lower part of my throw-out cylinder gasket, but it really didn't look like an adequate drain. So, I drilled a 3/32" hole in the bottom. Each time I look on my yearly spline checks, the inside of the cavity is clean, so nothing seems to be going in the hole.

 

By the way, there is a very nice DVD available showing in detail the changing of a clutch on an 1100RT. The 1150 is similar except for the hydraulic clutch.

[Peter Parts]

Thanks for reply.

 

But WHAT is the "bearing"? Is it a ball-bearing thrust bearing taking the load, a single ball the rod rests on, the pieces of the hydraulic cylinder, or what is it?

 

Ben

[OoPEZoO]

Thanks for reply.

 

But WHAT is the "bearing"? Is it a ball-bearing thrust bearing taking the load, a single ball the rod rests on, the pieces of the hydraulic cylinder, or what is it?

 

Ben

 

Its a standard ball bearing. It looks to be held in place with a snap ring on the R1150 and R1100S bikes. There would be a slight side load on the inner race of the bearing at all times, and much more when the clutch lever is pulled.

 

 

The R1100 bikes have a similar bearing, but it is pressed into a plastic or maybe Delrin (not sure) housing. Mine siezed on me last year at about 125k miles and started to spin the outer race in the housing. It didn't take long before my clutch lever was useless. It melted itself down into the housing. Below is what I pulled out. The bearing is supposed to sit flush with the top of the housing.

 

[AndyS]

Met up with the guy who is doing the trans.... He insists too that the alignment problems are inside the trans with a worn or misinstalled front or rear bearing....

So why would a worn bearing cause such major problems. If everything is concentric (and worn) then the shaft should be held pretty much in alignment by the clutch assembly.

If it a misaligned bearing inside the gearbox we would see wear on the internal parts. I just can't believe your 'expert'. How long will he guarantee his 'repair'?

Andy

 

[Peter Parts]

Thanks for reply.

 

But WHAT is the "bearing"? Is it a ball-bearing thrust bearing taking the load, a single ball the rod rests on, the pieces of the hydraulic cylinder, or what is it?

 

Ben

 

Its a standard ball bearing. It looks to be held in place with a snap ring on the R1150 and R1100S bikes. There would be a slight side load on the inner race of the bearing at all times, and much more when the clutch lever is pulled.

 

The R1100 bikes have a similar bearing, but it is pressed into a plastic or maybe Delrin (not sure) housing. Mine siezed on me last year at about 125k miles and started to spin the outer race in the housing. It didn't take long before my clutch lever was useless. It melted itself down into the housing. Below is what I pulled out. The bearing is supposed to sit flush with the top of the housing.

 

Thanks for reply.

 

Prolly a thrust bearing, not "standard"? The Delrin seems like a stupid idea in light of your own experience, although possibly intended to allow some movement of the rod to mate with the moving clutch pieces.

 

Sounds like the bearing needs grease from time to time... esp. for those from the wet-clutch crowd. Are the older or newer bearings sealed?

 

You mention R1100S - any difference between early bikes and later bikes in the Delrin matter? Or is the difference between models and bikes with hydraulic versus mechanical clutches?

 

Ben

[OoPEZoO]

very well could be a thrust bearing......I'm not a bearing guy, I'm an electronics guy. A thrust bearing would make more sense for the application.

 

I don't believe you can grease them. The face of the bearing appears to be sealed and can't be removed from the mechanical clutch bikes. You might be able to pull the snap ring on a hydrolic clutch bike, disassemle it, and grease it from the back side, but I have never seen it done.

 

The difference in design is between the mechanical and hydrolic clutch designs, not so much the age/vintage of the bike. I don't know if the older bikes actually use Delrin, but the housing had the same type of feel and texture. I also don't know what the hydrolic slave housing is made of. If I remember correctly, they are some type of metal, but I have only had my hands on one once for about 30 seconds.

[Wind Shadow]

First post for me. Just bought a 96 r1100rt with 37k. Didn't check close enough but found clutch is slipping. Looks good and dry at seam. Was incorrectly adjusted but correcting the adjustment didn't seem to help problem much. Neat ride!

[AndyS]

...bought a 96 r1100rt with 37k. Didn't check close enough but found clutch is slipping. Looks good and dry at seam. Was incorrectly adjusted but correcting the adjustment didn't seem to help problem much. Neat ride!

 

Welcome to the forum, why not fill out your profile a little more.

May I suggest you start your question in a new post as it is a different issue to the one in this thread. (maybe an adminstrator could move it?).

But just as a starter, your clutch is cable operated and we were really following a thread about an 1150 (Hydraulic clutch).

The first thing to look at is clutch adjustment done correctly at both the gearbox AND lever end. Is this how you did it?

 

Andy

[Wind Shadow]

Thanks for the directions Andy! Filled out the profile and will navigate around the site until I am a little more familiar with how to use.

I hope I can be a better mechanic with the bike than I am with the site.

I did the adjustment like the attachment you sent and I am still getting slippage.

[AndyS]

I did the adjustment like the attachment you sent and I am still getting slippage.

Well, it might be worth popping the starter motor off and take a gaze inside to see if you can see any problems on the visible parts of the clutch.