Clutch Spline Failure Analysis

[boxermania]

With due respect, the mechanic that ncator referred to doesn't know what he is talking about......and needs to quit if he is one of the Techs wrenching at Salt Lake City BMW.

[ASQTec]

....its bunk!

Well, maybe not entirely. Since only a small percentage of these bikes are prone to CS failure, one might assume that a rider's shifting technique can contribute to if and when it will happen. I think about that every time I shift.

[Lobo1625]

....its bunk!

Well, maybe not entirely. Since only a small percentage of these bikes are prone to CS failure, one might assume that a rider's shifting technique can contribute to if and when it will happen. I think about that every time I shift.

Any machine that is designed for the average consumer that doesn't allow for deviation in user style is not engineered correctly. I don't remember getting the memo for the class on how to properly shift the BMW I had just purchased. I understand that there may be a few cases of abuse that have lead to failure, but those should be so far and few between that it would be a 'freak incident'

[AndyRR]

I would be willing to bet this fellow just lost his clutch splines:
http://www.bmwbmw.org/bmwforums/viewtopic.php?t=12294

My bike is at 32k. Hoping it will make it to the winter for me to tear it apart and inspect.

[Trout]

...one might assume that a rider's shifting technique can contribute to if and when it will happen.

...I understand that there may be a few cases of abuse that have lead to failure, but those should be so far and few between that it would be a 'freak incident'.

I don't even think it's reasonable to assume that it could happen as a 'freak incident'.

Cars with manual transmissions get abused everyday. Even in drag racing applications, the idea that the clutch splines could get 'smoothed off' with abusive shifting techniques is unheard of. It just doesn't happen... the connecting rods can break, the axles can break, the valve train can come flying apart, the pistons can crack, the u-joints can come apart, but the lowly clutch splines on the trans input shaft and clutch disk remain intact... except on BMW R bikes.

[frbank6]

I think if I'm ever a victim of this, I'll just 'parts' out the bike rather than getting it fixed. It still infuriates me that BMW won't acknowledge there is any problem. I bought my bike based on their reputation for reliability. I thought that was what I was buying with the price premium. If I'm not getting that, and indeed, if I'm to be ignored when this type of problem crops up, I might as well save some cash and go Japanese.

I hoped to take some long, multi-state trips on my bike. Now, I'm afraid to leave home without the Anonymous Book and a cell phone.

Also, given the fact that in terms of numbers there can't be that many bikes that would be subject to recall for this, it would not be that expensive for BMW to fix them all or extend the warranty. Instead, their reputation is suffering, probably forever. As I mentioned earlier, when my employer saw potential troubles with a product line, they nipped it in the bud, took their lumps and most importantly, took care of their customers. If a tractor company can do that, I think BMW could, too.

[Just-Beeming]

Any machine that is designed for the average consumer that doesn't allow for deviation in user style is not engineered correctly. I don't remember getting the memo for the class on how to properly shift the BMW I had just purchased. I understand that there may be a few cases of abuse that have lead to failure, but those should be so far and few between that it would be a 'freak incident'

I quite concur!!!!

I don't grind it, I don't dump it,I don't burn it, I don't slip it.... heck I don't even clunk it. I am a smooth, positive shifter...I have always felt pretty proud of my shifting!
'User Abuse' is a scapegoat approach to a big big problem. There should be NOTHING I can do to destroy this bike under normal road riding conditions...other than normal expected wear and tear.

I am so concerned about it happening again... I will fear failure on long road trips! A design flaw is not something I can just fix and feel secure about... What assurance can I have that this will not happen again as it did with Tor1150R???

Time for this girl to go shopping for a new bike....

[vexlak]

Could we somehow file a lawsuit against BMW? I understand that the products are out of warranty however if we can prove that there is a failure and they are aware of it, something will come out of it. In addition, BMW would not like the negative publicity. What else is there to do? Nothing to loose…

[jpsmith]

Chalk up an other early failure. 28,xxx miles of easy riding. Does this problem extend into the R12RT models? Jim

[jpsmith]

I would be willing to bet this fellow just lost his clutch splines:
http://www.bmwbmw.org/bmwforums/viewtopic.php?t=12294

My bike is at 32k. Hoping it will make it to the winter for me to tear it apart and inspect.

Yes I did.... not a happy camper either. It just took me a while to find my way here.
I'm in with the class action move. But I think that it would be hard to get manufacturing and maintenance records out of BMW since they are off shore. Jim

[iowabeakster]

Sorry to hear about your problem, jpsmith.

I don't know about the 1200's. They are a whole different bike, and don't have the miles and years of the 1150's out there. The 1150RT seems to be the most affected.

What is there to do? We don't know if this is rare or common. Until the parts are examined, a "problem free" bike with 50K or 75K miles might be hanging on by a thread. So now what, find a few thousand voluteers to tear their bikes apart? Then we can find what percentage are problematic without waiting for total failures to amass.

I want to take a look at mine.

[djskriff]

So, I'm a first time rider who made the plunge for an '04 R1150R w/ 30.5k miles on the odo about a month ago. I've noticed increased misses in upshifting 1-2 after a single incident about three weeks ago.

I was accelerating hard, ~6000 in first, when I made this amateur mistake - I let the engine spool down to approx 2500-3000 before attempting the upshift. The difference in the engine and drive speeds, I presume, led to a deluge of metallic chatter and noise that I thought killed the clutch for sure. However, once I rolled into a driveway and cycled the engine on and off, I took off once again with no problem.

I've been able (although unintentionally and in traffic) to reproduce this difficulty in upshifting 1-2 on at least two occasions since. Not as loud as the first one, and with careful rev-matching, 2nd can be engaged with no problem at this higher speed.

Anybody else think this sounds like a clutch spline failure waiting to happen? I'm up to 31.8k miles now and I'd really *prefer* to not be broken down in a couple of weeks when I make my next journey.

I, like many others, justified the premium pricing on the BMW moto based on BRAND RELIABILITY and PERFORMANCE. A dead tranny throws both of those out the window...

[MikeCam]

Boxermania is doing a good job exploring the variety of items that appear related to this problem. Keep him in the loop. Unless the number of incidents reaches 1%, it will be a hard job convincing any U.S. agency that an issue exists.

[Lobo1625]

I finally tore into my 2002 R last night with the help of another board member. The results at first sunned me. My splines looks fairly good... There was wear after 9900 miles, the token shiny spots were starting to form and slipping the disk on and off the splines did result in a bit of a 'hang' or 'catch' where the disk rides. There was still lubrication on the splines, a white grease or one brand or another, but not dry, as was the last bike (also a 2002, 100 apart in the built according to the vin) There was however no grease on the other friction areas of the clutch where the spring rides or where the clutch rod engages the pressure plate. All this good news couldn't be without its bad however. I have a leaky clutch slave cylinder. I had noticed the clutch felt 'different' the last few times i was on the bike but hadn't made the connection. (does however make sense why I had to adjust the clutch lever for more throw)

I'm going to take one of the bad clutch disks I have and try to get a new center hub made next week. I noticed on mine that the hub is cast then machined. The one that came off my bike looks terrible, but it explains the weak metallurgy. I'll take pictures of mine to support this theory. If ANYONE knows where I might have some luck finding data on the splines used on the bike. I'll post pictures of the teardown as soon any any more info as it comes along.

I think this evidence alone should help support a few different things. It's certainly not rider style as my bike has spent several hours on a dyno, and I've not babied it when I ride. There is a QC issue with BMW as this bike has grease on the splines and yet one built less than 100 away in the production was bone dry. Even after 6 years there was still some grease there on my bike. The part number of the clutch disk does show wear in the 'usual' spots and had a 'hang' in it, which is quite disappointing after so few miles.

Also I have no taken any runout or concentricity readings on the bike yet, but as there was minimal wear I am fairly sure that it's spot on. I'll find out later this week/weekend. Also for those of you who are wondering, the whole teardown process took 2 people about 2.5 hours. It's really pretty simple and just knowing which bolts to take out helps. I'll do some photos that show what to remove to try and help others.

[sweatmark]

Lobo - great info, thanks. If problems don't appear in the mean time, then I'll be doing the inspection on our '02 and '04 R1150Rs this winter. And I've got a bad feeling about the '02... first manufacturing year (USA) for the hydraulics and clutch slave cylinder application, first year with a bit more torque than the R1100 bikes, plus we've got 24K miles on the bike at present.

So remind me, what are the options for the slave cylinder? Seal replacement? Or the entire piece? And the CycleRob tell-tale notch, of course.

[Twempie]

So, I'm a first time rider who made the plunge for an '04 R1150R w/ 30.5k miles on the odo about a month ago. I've noticed increased misses in upshifting 1-2 after a single incident about three weeks ago.

This sounds like my bike. I have 28k on my 03 RR. A thread on the MOA site suggested preloading the gearshift, and I have to tell you it works, and the technique is easy to get used to. Just put a bit of pressure on the gearshift just before upshifting and you won't miss 2nd gear. Do this throughout the gears and you'll think you're on a Honda

[awagnon]

So remind me, what are the options for the slave cylinder? Seal replacement? Or the entire piece? And the CycleRob tell-tale notch, of course.

I believe you have to replace the entire slave cylinder. When mine failed, I couldn't find a rebuild kit. Also, the hydraulic hose was leaking where the banjo connector attaches to the hose on the slave end. This, apparently, is a not an uncommon place to leak due to rusting of the connector.

[johnnyjs1]

04 Rockster with 16k down. Chalk another one up for the stats

[towerworker]

Lobo1625--

I'm certain I am with many others who would be very much interested in seeing your teardown pics and procedures. I have an 04 with 25K and definitely plan to do a teardown inspection this winter. I have had 0 problems with my 04 and the same with 42K on an 03. But all this talk of CS problems has me a tad concerned. Would much rather catch a potential problem when I am prepared to do something about it. Thanks again!

Wayne

[sweatmark]

Spent a little free time catching up on the spline threads in ADV, where there's an interesting failure after only 1800 miles on the clutch and transmission input shaft (albeit used tranny). Pictures are included in the thread (sorry, didn't grab the URL).

Somebody here tell me how I'm wrong here: what about the dynamic balance of the clutch disk? I see how the clutch hub is somewhat cantilevered on the transmission input spline (kind of a technical "stretch" - I know), and wonder how out-of-plane vibration of the clutch disk when not engaged with flywheel might manifest itself as small zone stresses that exceed the clutch hub and shaft's strength limits.