Clutch Spline Failure Analysis

[Yep]

Another one here- '04 with 12,999 on the clock.

Mainly commute rider.

Has anyone attempted to have this failure covered via an extended service contract?

[RonBomb]

This is an excellent analysis. The only question I have is what are the signs of impending failure? Is there anything noticeable?

[iowabeakster]

Yep,

13 thousand miles!

Please check out the first thread at the top of this section: "Clutch spline failures - Let's get serious." Boxermania would like some basic information, as he is compiling facts about as many failures as he can.

[Tlaloc]

Mine (2002) happened in July 2007 at 15,225 miles, while on what was supposed to be the last leg of a 3000 mile trip. The BMW dealership that replaced the clutch botched the job, had to have the transmission replaced by my hometown dealership upon my return. Since then I've put on over 7000 miles with no trouble.

[Yep]

Another one here- '04 with 12,999 on the clock.

Mainly commute rider.

Has anyone attempted to have this failure covered via an extended service contract?

Confirmed failures:
Slave cylinder
Splines on input shaft- gone
Splines on clutch plate- gone
Final Drive seal- leaking

Complete failure due to NO lube- none, zero.
Alignment looked good, will need to re-shim during repair.
Shop indicates recent failures through them have been lube related, not allignment.
Working through extended service company now- hoping some of damage will be covered, waiting on adjuster to visit the shop
Estimate is $3,200

[Just-Beeming]

this is really ticking me off....

I still don't have my bike back and I still don't have official word of cause nor do I have any assurance that problem will be REALLY corrected.... since we don't really know if it is too short of shaft, lack of lube, metalurgy or misalignment....

Today is just 5 days short of happening one month ago....my summer is ticking away...

Every summer riding season that is wasted is ONE I DON'T GET BACK!!!!!! I am ticked!

Where is Motorcycle Consumer News on this...they did a nice write up on Final drive failures but we need them to investigate clutch spline failures as well...my gut tells is that the numbers are big and getting bigger as we the riders accumulate miles.

[awagnon]

Where is Motorcycle Consumer News on this...they did a nice write up on Final drive failures but we need them to investigate clutch spline failures as well...my gut tells is that the numbers are big and getting bigger as we the riders accumulate miles.

I may be wrong, but I believe the BMW final drive failures showed up in MCN because it happened to one of their contributing writers. Also, FD failures might actually be more common than spline failures, but certainly not as difficult or expensive to fix. What's worse, spline failures are showing up after the warranty expires leaving the owner on their own. DAMHIK

[jpsmith]

In reference to my earlier post; Yep, just what I expected to see when I tore it down this morning. A total spline failure. 2004 R1150RT 28,620 miles.





I think that the clutch will be the easy part of this repair. If the nose on the clutch hub was just 3/8" longer it may help, or slow the problem. Obviously there are (were) misalignment issues here. Metal fatigue is what it looks like to me.
I don't think lube is the solution to this problem. It is only intended to prevent corrosion on the splines and aid in the smooth in / out operation of the clutch. Remember this is not a gear, it is a spline and shaft. Two completely different animals with completey different stress elements.
I have a 3/4" spline shaft for the mower drive PTO on my tractor that has been in service for 20 years and has never been lubed. Neither have the mated gear and chain links that hold it together. I had to disassemble it to replace a fan belt. It was dirty and rusty, but there was only minimal wear. Just my 2 cents into the wishing well. Jim

[iowabeakster]

Jim,

Thanks for taking the time to post those pictures. They look identical to pictures posted by several others here.

If you (and Tlaloc, Yep, and anybody else with spline failures) haven't already, PLEASE check the "sticky" thread at the top called "Clutch splines- let's get serious". Boxermania is collecting information. Either Boxermania or Lobo would like to examine the parts too.

[sweatmark]

Just-Beeming: is your bike at the Tigard store?

Admins: is it possible to roll this thread's info into the sticky spline-failure thread that's now at top of the page? Just thinking it would be helpful to have all the related info for this important topic in one place. Same goes for the info in the current "Disaster!!!" thread started by johnnyjs1 pertaining to same topic.

FWIW - It has been stated that the transmission input splined shaft has been chrome-plated since early '90s. I'm wondering if this practice was impacted by the EU regulations concerning chromium that changed corrosion- and wear-resitant metal parts coatings around 2002. Might a change in this aspect of parts finishing have impacted the transmission input spline's potential lifespan?

http://findarticles.com/p/articles/mi_m ... i_95526310

Also, the concept of "fretting" popped in during some online research. Given the cantilevered clutch hub and variations in amount of spline lubricant witnessed by owners during spline inpections, might fretting be a potential cause of failures?

http://en.wikipedia.org/wiki/Fretting

Finally, does anyone know if dynamic balance of dry clutches is part of product QC testing?

<edit - added URL for chromium info>

[Just-Beeming]

Sweatmark
No it is at Portland. My bike service has always been done there as I owned the bike before Scot and Madelyn came to Tigard.

[boxermania]

sweatmark

Regarding the chrome issue, I don't know if the input shaft splines are coated, however, my background with metl coatings that chrome, due to the micro-fractures on it's surface (after application that is) would not be, IMO, a good coating for this application.

Moving on and regarding the forces present at the interaction betweenthe clutch disc and the input shaft anything goes.....you have a rotational force against one side of the tooth, the same against the other side, upon coasting. Then you have a rocking moment (front to rear) as the result of the clutch disc overhanging the input shaft splines. Last but not least ,you have the force component added by the input shaft not being kept in check by the rear of the crankshaft as is typical of all dry clutch applications since it's introduction.

Fretting, in this instace and based on the above paragraph an certainly be looked upon as a contributory factor.

Typicaly, clutches in this diameter and relatively small weight are not balanced.....the lsignificantly larger mass components, suach as the flywheel and pressure plate are.

Good post........

[sweatmark]

Typicaly, clutches in this diameter and relatively small weight are not balanced.....

Which is what I would expect for something like a small clutch, for which some dynamic instability due to imbalance would not normally cause problems with full engagement of the splined hub and shaft surfaces. But for the R1150** clutch/shaft arrangement, whose splined surfaces are not fully engaged due to the cantilever/overhang/mismatch of transmission input shaft length, the potential for out-of-plane clutch wobble could be a cause of the spline wear problem: every time the clutch plate is pushed away from flywheel by diaphragm spring, there's potential for wobble if the spline tolerances allow, and rotating components are imbalanced.

Those "wobble forces" could be great with higher RPM and loose tolerances on the hub & shaft. More wear, more wobble. Shampoo, rinse, repeat - as it says on the bottle. The wobble-correcting forces would be highest in the contact zone at end of transmission input shaft and mating surfaces in clutch hub, and at the rearward end of clutch hub facing transmission body, that section of the input shaft that indeed shows the most wear. "Fretting" would be one possible description of the wear mechanism.

Just an idea.

[Just-Beeming]

It is down to the wire on my bike. It is currently just a matter of hours before I get the final word on what BMW will stand by, how my dealer will explain the problem, what the cost of repair is.
My dealership has been great through this process. Kind, in fact, showing some empathy for what I have been dealing with.

Of course my emotional trust factor with the bike is still on shakey ground, I will put some miles on it this weekend to see how it all goes for me.

More to follow as I get breaking news.

JB

[sweatmark]

JB - please let us know the results.

I will say one good thing about all of this spline stuff: it provides some good drama.

It's also provided fodder for many a conversation regarding quality, customer support, and brand loyalty. Like many of you out there, these fundamental business concepts are part & parcel of my everyday worklife, and I hope I'm learning something through hobby that applies to the job.

[MattPie]

Where is Motorcycle Consumer News on this...they did a nice write up on Final drive failures but we need them to investigate clutch spline failures as well...my gut tells is that the numbers are big and getting bigger as we the riders accumulate miles.

Shortly after reading the MCN article, I send an 'letter (email) to the editor', referencing these threads. Never head back, but we'll see. I encourage everyone else to send an email about this subject, especially those directly affected.

[Just-Beeming]

I have a letter ready to send as soon as I know the outcome of my own situation.
I want to be careful to give facts and not emotion...
allthough the emotion that accompanies this failiure is big business for BMW.
The failure is only part of the problem...the way BMW deals with it may be the other half of the equation.

Thanks for the great Idea...If you have suffered a spline failure...jot a few words to MCN....

I will as soon as this is wrapped up.

[GypsyRR]

Why are there more occurrences of this happening with RTs than the RRs?

[MattPie]

Why are there more occurrences of this happening with RTs than the RRs?

I would *guess* it's because the RT is heavier. The drive-train has to work harder to move the bike. Working harder == more friction when things are sliding against each other, and more friction == more wear.

[MattPie]

I have a letter ready to send as soon as I know the outcome of my own situation.
I want to be careful to give facts and not emotion...
allthough the emotion that accompanies this failiure is big business for BMW.
The failure is only part of the problem...the way BMW deals with it may be the other half of the equation.

Thanks for the great Idea...If you have suffered a spline failure...jot a few words to MCN....

Yeah, I tried to be rational about the whole thing. Just thanked them for the FD article, mentioned that I was worried about the clutch spline issues, and sent them a few links to the discussions here. If they're interested that should give them a pretty good start, especially if they start following links from here to other sites.