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tranny input shaft

bsample

New member
My 04 1150rt with 57k has had the clutch rattle since I bought it at 51K. So I pulled it all to take a looksee and hoped I could get by with a lube job- however, the input splines are pretty worn and I'm not comfortable putting in a new clutch and re installing it. Apparently there is a redesigned input shaft available at about $1k that utilizes the full clutch collar, or a redesigned clutch that has a longer collar at $600 that fully engages the input shaft. Either way I'm going to need both the shaft and clutch pak. Anyone been in a similar predicament and have advice?

I have experience with dry clutches on auto's, and have never seen a design that did not fully engage the clutch on the splines. Blows my mind that BMW would put something like this on the road and not have remedied it with better designed replacement parts, much less even admit it was a problem. I love this bike... and if I put it back together stock I know I'd be looking at the same thing down the road- hopefully not on the side of the road. I thought I'd got lucky when I found a local dismantler that had a gearbox with 38K on it, but it only looks marginally better. He told me that if it was as good as he has seen after taking many of these bikes apart, and that if I wanted any better I would have to get a new shaft. I suspect it would have gone another 30 or 40k, but then I'd be in the same boat- or on side of the road.

Any experience with the "improved" parts?
 
It is my understanding only one or two of the "improved" tranny input shafts were produced in Canada. Only one was installed and to my knowledge, there hasn't been a report on the longevity of the shaft. Someone please correct me if I'm wrong. The $900 price was too steep for most and availability was an issue. The splines went out of my 1150RT at 42,000 miles, which is a little longer than most. I would have paid $900 for the shaft if it had been available. I'm currently watching the splines on my "04 1150GS. There was significant wear two years ago and I'll be taking another look in a couple of weeks. It was a very poor design.
 
Al, splines dying around 40K miles is indicative of a trans/motor misalignment. If left unfixed, that misalignment will continue to cause shafts and clutches to eat each other every 40K or less, forever. Some suffer from that, others suffer from poor/missing/dry lube which causes excessive wear. Those usually die somewhere north of 60K. Preemptive lubing every 40K will prevent the latter situation.

My understanding on the Canadian shafts is the same as yours. The maker claims big miles on the one he installed for himself, but no to few others were ever made, to the best of my knowledge.
 
It is my understanding only one or two of the "improved" tranny input shafts were produced in Canada. Only one was installed and to my knowledge, there hasn't been a report on the longevity of the shaft. Someone please correct me if I'm wrong. The $900 price was too steep for most and availability was an issue. The splines went out of my 1150RT at 42,000 miles, which is a little longer than most. I would have paid $900 for the shaft if it had been available. I'm currently watching the splines on my "04 1150GS. There was significant wear two years ago and I'll be taking another look in a couple of weeks. It was a very poor design.

You are correct.
As far as availability goes.....
I could not get a group of 10 to commit to a batch run.
I am still testing and am at about 65,000 miles.
So far there is no radial slop in the plate and all looks good.
Gotta ride more.:dance
 
Al, splines dying around 40K miles is indicative of a trans/motor misalignment. If left unfixed, that misalignment will continue to cause shafts and clutches to eat each other every 40K or less, forever. Some suffer from that, others suffer from poor/missing/dry lube which causes excessive wear. Those usually die somewhere north of 60K. Preemptive lubing every 40K will prevent the latter situation.

My understanding on the Canadian shafts is the same as yours. The maker claims big miles on the one he installed for himself, but no to few others were ever made, to the best of my knowledge.

In actuality they are quite different from a metallurgy and tolerance perspective. Not to mention being 6mm longer.
 
Incredible. A beautiful motorcycle with a nearly fatal flaw (fatal from the cost of labor and parts to repair it, not to the rider).
Anyone ever heard BMW's excuse for this monumentally poor design/assembly decision? I wonder if anyone in Berlin ever lost their job over that one.
 
Incredible. A beautiful motorcycle with a nearly fatal flaw (fatal from the cost of labor and parts to repair it, not to the rider).
Anyone ever heard BMW's excuse for this monumentally poor design/assembly decision? I wonder if anyone in Berlin ever lost their job over that one.

It is not the Teutonic nature to admit wrong.......it goes along way back
 
The splines not making full contact in oilheads seems to me an obvious mistake and I can't view it any other way. There is room for full engagement, every other design like this makes full engagement even other BMW models so what other plausible conclusion can be made other than someone made a boo boo. I think GSAddict has made and installed the ideal solution and while some say it's too expensive at $900, a $600 extended clutch hub is not that much cheaper. I think the spline fix would be stronger. At 65K he's already well beyond the typical failure mileage of many of the catastrophes we've read about here.

Chris Harris from Affordable Beemer Shop alludes to three fixes for the typical oilhead spline failures and has done a video on his theories here: http://www.youtube.com/watch?v=Jx3e0gqzylY

Chris curses a lot and has a gruff (is that a word?) way about him but he is an experienced repair guy and a lot of stuff in his videos is useful. One of the 3 solutions he proposes is a clutch disc that has an extended hub that makes full contact with the input shaft. Some would argue this is easier than replacing input shafts. I have to agree. A picture of one of these extended hub clutches was posted here recently?? and they are made by Bruno's. Not found on Bruno's website but that is where they come from.
Contact Details:
Bruno's Machine & Repair
HWY 554 # 47
RR1 Iron Bridge, Ontario
P0R1H0 Canada
phone / fax 705 843 0822
E-mail: brunos@brunos.us
 
Al, splines dying around 40K miles is indicative of a trans/motor misalignment. If left unfixed, that misalignment will continue to cause shafts and clutches to eat each other every 40K or less, forever.

I agree, Bikerfish, but I didn't have the gigs, tools, or gauges to check for axil misalignment. So I did the next best thing and replaced everything else ( Clutch housing, input shaft, input shaft bearing, all clutch parts ) in the hope that the problem was with flywheel runout. I sold the bike (a 2002 1150RT) 30,000 miles later and everything was still doing well. I warned the buyer, who is an engineer, that the splines might crap out again in 10,000 miles. He was willing to take the chance for the great price. Still all is well. My 2004 1150GS is the one I'm just watching. I wouldn't be surprised if I don't end up replacing the input shaft this winter.
 
It is not the Teutonic nature to admit wrong.......it goes along way back

I has been my observation that it goes farther than this. It is also the Teutonic nature to do it wrong again if doing it right could be misconstrued as admitting the first design was not absolutely perfect and that includes ignoring any and all facts to the contrary.

Rod
 
Incredible. A beautiful motorcycle with a nearly fatal flaw (fatal from the cost of labor and parts to repair it, not to the rider).
Anyone ever heard BMW's excuse for this monumentally poor design/assembly decision? I wonder if anyone in Berlin ever lost their job over that one.

Problem? Zere ist no problem.
 
I has been my observation that it goes farther than this. It is also the Teutonic nature to do it wrong again if doing it right could be misconstrued as admitting the first design was not absolutely perfect and that includes ignoring any and all facts to the contrary.

Rod

And THAT is exactly why they lost the big one.:laugh
 
Back to splines, short shafts, small hubs, and failure!! Yes the design sucks! But they don't all fail, and certainly not all at an early age. My R1150R is at 170,000 miles on the originals as out of the factory. True, when last looked at and cleaned and lubed at 160,000 miles or so they were not as pristine as I wanted to see but still worth putting the bike back together without new parts.
 
Back to splines, short shafts, small hubs, and failure!! Yes the design sucks! But they don't all fail, and certainly not all at an early age. My R1150R is at 170,000 miles on the originals as out of the factory. True, when last looked at and cleaned and lubed at 160,000 miles or so they were not as pristine as I wanted to see but still worth putting the bike back together without new parts.

Paul, I know from your posts that you've kept your splines clean (no grit in the mix) and lubricated (less wear and corrosion). I'm also going to guess that you know how to treat machinery and that your bike never had its clutch abused in any way. Perhaps a combination of those factors along with good clutch housing flatness and shaft alignment kept your bike from being affected. RB
 
Back to splines, short shafts, small hubs, and failure!! Yes the design sucks! But they don't all fail, and certainly not all at an early age. My R1150R is at 170,000 miles on the originals as out of the factory. True, when last looked at and cleaned and lubed at 160,000 miles or so they were not as pristine as I wanted to see but still worth putting the bike back together without new parts.
The input shaft is probably hardest at the tip. Properly aligned, this spline set is completely adequate.

If there is a radial manufacturing or assembly error, it requires frequent attention and relubrication (if any was applied at the factory. If the radial alignment error is substantial, the spline OD teeth will wear the hub teeth at the engine end until they eventually begin to strip out, shifting the contacts to the transmission end. Then the remaining spline at the transmission end in the hub finally strips out giving the characteristic major wear at the transmission end of the shaft. The advanced wear pattern is what causes the clutch to hang up on the shaft making shifting awkward. If you have gotten to the point of messy shifts, the hub is about ready to let go.

Note how little spline it takes for the last bit of wear, indicating the ability of this spline to handle the torque. I suspect that a substantially worn shaft could be re used again with only a minor reduction in life especially if the alignment is corrected (assuming the crankshaft main bearings are still OK).

But it is the radial alignment error starts the whole process. Not the shaft engagement.
 
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Back to splines, short shafts, small hubs, and failure!! Yes the design sucks! But they don't all fail, and certainly not all at an early age. My R1150R is at 170,000 miles on the originals as out of the factory. True, when last looked at and cleaned and lubed at 160,000 miles or so they were not as pristine as I wanted to see but still worth putting the bike back together without new parts.

Paul, your bike has considerable mileage. Quite likely more then most of us will ever obtain. I am very curious if your seeing even wear along the length of the spline? Or like many of us, more wear at the transmission end of the spline.
 
Just searched ebay for motorcycle - BMW transmission and got over 600 hits.
If what you need isn't on there or at Beemerboneyard this week it will be.
Insurance companies total bikes for anything more than scratched mirrors so plenty of good used parts available.
 
96 R1100 RT 5 speed box

Is there drawings or a fixture to check alignment? Are alignment dowels available thru a source or should I get a local machine shop to make a set depending on what I find. Also best place to pick up a good quality alignment tool for the clutch assy?

I think my baby's 1st spline lube is due, as soon as I clear garage and bench space she will be coming apart for inspection and a good bit of maintenance.

Thanks all
Dadrider.
 
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