BMWSportTouring

R1150r rockster spline/gearbox integrity

Posted By: eliastfk93

R1150r rockster spline/gearbox integrity - 11/29/17 07:55 PM

I ride an 04 r1150 rockster, and was wondering if there are any durability issues to worry about with my splines or gearbox. I was under the impression that the rocksters came with the short ratio gearbox from the GSA's....does this make it more solid? I'm at 35k and I commute daily . I've changed the rear diff and gearbox oil, and don't feel anything out of the ordinary, I'm just curious.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 11/29/17 08:33 PM

Originally Posted by eliastfk93
I ride an 04 r1150 rockster, and was wondering if there are any durability issues to worry about with my splines or gearbox. I was under the impression that the rocksters came with the short ratio gearbox from the GSA's....does this make it more solid? I'm at 35k and I commute daily . I've changed the rear diff and gearbox oil, and don't feel anything out of the ordinary, I'm just curious.



Afternoon eliastfk93

Gearbox ratios don't seem to have any effect on spline failures as it is mostly an alignment issue that causes the failures. (the 2004 bikes seem to be better than the earlier 1150 bikes)

At 35K you are just coming up on the end mileage of most early 1150 spline failures (not that they can't happen at a later mileage but most chronic early failures come at slightly earlier mileage).

If you are worried just remove the starter, then zip tie the clutch lever to the handlebar, then use a sharp pick or long thin screwdriver & see how much clutch disk rotation you have on the spline shaft prior to the spline shaft starting to rotate.
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 11/30/17 12:36 AM

I picked up an '04 Rockster recently with 32k miles on it. While it seemed fine with no issues I proactively pulled the gearbox to inspect/lube the splines and found them heavily worn. The disk splines were about 80% gone.

The sport g'box differs from the std only by a shorter 6th gear.
Posted By: eliastfk93

Re: R1150r rockster spline/gearbox integrity - 11/30/17 05:02 AM

Thanks dirtrider and Craig G! All seems well so far. It's the been the best "do everything" bike I could ever ask for. I commute almost daily, I've taken 1200 mile touring drip along the gulf coast, and its got so much character. Oh yeah, my last bike was an 04 r1150r standard model, and it had 48,000 miles when I got rid of it and there were no issues of the sort. I just wondered if the rocksters differed at all in that department.
Posted By: Jim Moore

Re: R1150r rockster spline/gearbox integrity - 11/30/17 10:44 AM

The problem is this. If you have a good one, it will last a long, long time. If you have a bad one, it will go bad between 30,000 and 40,000 miles. It will feel just like a good one, right up to the point when the splines strip out and leave you on the side of the road staring at a multi-thousand dollar repair bill. If you have some mechanical skills it is well worth the time and effort to check it out, as DR recommended above. There are enough bad ones out there to warrant taking a peek.
Posted By: Mark C

Re: R1150r rockster spline/gearbox integrity - 12/03/17 04:05 PM

I just pulled an 02 R1150Rt with 90k.
The clutch and transmission splines were dry as a bone.
There was zero problems with it's function.
I agreed that some make it and some don't.
I am beginning to suspect the newer thinner flywheel that started with 2002 could be the problem and allows wobble of pressure plates?
It appears the grease & lubrication made no difference to this one.
If anyone wants to see pictures, let me know. I can't find an attachment link here?
Mark
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 12/03/17 08:06 PM

Originally Posted by Mark C

I am beginning to suspect the newer thinner flywheel that started with 2002 could be the problem and allows wobble of pressure plates?


I'd love it if could be explained that easily.... the question then is why do so many (post 2002) go the distance without issue.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/03/17 08:33 PM

Originally Posted by Craig G.
Originally Posted by Mark C

I am beginning to suspect the newer thinner flywheel that started with 2002 could be the problem and allows wobble of pressure plates?


I'd love it if could be explained that easily.... the question then is why do so many (post 2002) go the distance without issue.


Afternoon Craig G

Wobble would give us asymmetrical spline wear patterns with an uneven wear pattern at different clocking's on the spline shaft.

All the BMW 1150 spline wear that I have seen is very symmetrical with an even matching taper on all the individual splines & that indicates an alignment issue not a wobble issue.

The question is: what causes the mis-alignment on some & not on others. Is it a manufacturing tolerance stack-up problem, or a parts quality problem, or a shipping problem (shipping crate mis-handling/dropping during shipping as bikes were crated with no front wheel installed), or even an engine (crankshaft location in relation to alignments dowels) problem, or ????????
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 12/03/17 10:16 PM

DR... I think your above response was intended for Mark C, not me. My response to him casts doubt on the wobble theory.

I have a number of theories concerning this issue and am methodically working my way to evaluate a posible solution... not meaning I'll ever understand root cause. Making use of mods available to provide full spline engagement is the start. Just need to accrue miles to evaluate the mods.
Posted By: Mark C

Re: R1150r rockster spline/gearbox integrity - 12/04/17 01:32 AM

I did that mod with no improvement.
A VW mechanic told me they had Rabbit Diesel do this too, they were told to shim . One of the no see problems with BMW using the trans housing as a bell housing. Once it's plugged in, you can't see . Funny how BMW went to a top plastic inspection cover on Hexheads?
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/04/17 02:07 AM

DR has the reasons for spline wear pretty well covered above.

I would add though that there may be an assembly technique combined with the flimsiness of the clutch bell housing - i. e. that big hole to holding the starter that interrupts the engine-side flange. The alignment spools are very short and have only a very short engagement that just might make them marginally prone to cocking when exposed to shear side loads during final assembly pullup.

If the engine - clutch disk - transmission alignment is perfect - the final assembly will maintain alignment as the engine-transmission bolts are drawn up. But if the clutch disk/pack is poorly centered in the flywheel, drawing up the engine transmission bolts will force the clutch disk to drag across the flywheel face possibly cocking those alignment spools. It probably takes over 1000 pounds shear force to drag the clutch disk that way, and would be enough to distort the bell housing with its open section.

A possible solution to a possible problem - insert the clutch release rod and only assemble the transmission to the engine with the clutch pulled in.

Only someone with a lot of field or service experience might be able to verify or disprove these possibilities. I don't have that experience, but am looking at it from the standpoint of 50 years of chasing mechanical engineering screwups.
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 12/04/17 08:27 AM

Originally Posted by Mark C
I did that mod with no improvement.


Mark - pls elaborate. What specifically did you do and what were the results?
Posted By: Alan Sykes

Re: R1150r rockster spline/gearbox integrity - 12/04/17 02:02 PM

I think you're right, NRP. My middle son is a Beemer Motorrad trained wrencher and he says it was definitely factory misalignment during assembly that caused premature spline wear on a smallish batch of 1150 machines.
A problem which the factory consistently refused to either acknowledge or address and was solved by them in later models by the almost total re-design of the motor and transmission units, incorporating the Chinese wet clutch.
Tim was taught in his callow youth years in the training school, NEVER to pull up a gearbox / FD unit to the bell housing in any vehicle re-assembly procedure by heaving on the bell-housing attachment bolts. The two elements must be pushed up together into correct alignment by hand, using the clutch push rod as a centring tool - i.e, the hard way requiring muscle - before attending to any bell-housing bolt torque-values.
And Dirt Riders's tip of how to check spline condition easily and quickly by removing the starter motor is a good 'un.
AL in s.e. Spain.
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 12/04/17 02:23 PM

Originally Posted by Alan Sykes
solved by them in later models by the almost total re-design of the motor and transmission units, incorporating the Chinese wet clutch
.


No doubt you're refering to the wet head design in the above statement. Makes me ask the question... do camheads or hexheads experience spline failure similiar to the 1150?
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/04/17 02:43 PM

Originally Posted by Craig G.
Originally Posted by Alan Sykes
solved by them in later models by the almost total re-design of the motor and transmission units, incorporating the Chinese wet clutch
.


No doubt you're refering to the wet head design in the above statement. Makes me ask the question... do camheads or hexheads experience spline failure similiar to the 1150?


Morning Craig G

I haven't seen (or know of) a camhead with spline failure. (there might be some but none that I know of in my area or riding groups)

I do know of 2 hexheads (both over 100K) with one having total spline failure & the other needing a new clutch & splines were found to be worn pretty bad at disassembly.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/04/17 03:04 PM

Originally Posted by Alan Sykes
I think you're right, NRP. My middle son is a Beemer Motorrad trained wrencher and he says it was definitely factory misalignment during assembly that caused premature spline wear on a smallish batch of 1150 machines.
A problem which the factory consistently refused to either acknowledge or address and was solved by them in later models by the almost total re-design of the motor and transmission units, incorporating the Chinese wet clutch.
Tim was taught in his callow youth years in the training school, NEVER to pull up a gearbox / FD unit to the bell housing in any vehicle re-assembly procedure by heaving on the bell-housing attachment bolts. The two elements must be pushed up together into correct alignment by hand, using the clutch push rod as a centring tool - i.e, the hard way requiring muscle - before attending to any bell-housing bolt torque-values.
And Dirt Riders's tip of how to check spline condition easily and quickly by removing the starter motor is a good 'un.
AL in s.e. Spain.


Morning Al

Common sense tells me there is no real credibility to some of the above.

First off we have no idea that the problem was at assembly. On some of the worn spline bikes I have seen way too much trans to engine misalignment to be a simple assembly issue. It usually takes a new front trans housing or offset alignment dowels to allow alignment so THAT doesn't point to an assembly issue.

Next, if it was an assembly issue then why would it take a re-design to cure the problem. All it would take is a simple assembly procedure change then monitoring. I would be willing to bet a lot that BMW took a serious look at assembly & handling/fixturing procedures at the first sign of warranty spline issues.

Then we have the re-occurring spline failures on the same bikes at about the same mileage-- Do all the dealer tecs use the same poor assembly procedure & if that is true then why don't we see lot of 1100 bikes with spline failures after a new clutch install?

Next, you never ever use the pushrod for transmission centering/alignment as that is a good way to end up with a bent pushrod. BMW has a special clutch disk centering tool & if used correctly the trans will usually slide right in without the need for any force or push rod use.
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/04/17 09:53 PM

Afternoon D.R. -

You are on the right track on this problem and I appreciate that someone understands what I have been bitching about for the last maybe 6 years..

I don't think BMW technicians ever figured out the spline wear problem. Somewhere in the management of all this warranty and service problem, there has been a high level assumption made that no one at lower levels really thought about and defended the problem and its source to management. And this is why the design approach was radically revised As an example, the number of posted theories and red herrings that have come up on this issue over the last 15 years suggest that it is not a simple deal. One that seems to be missed by many is the barrel shaped wear pattern that is said is due to flywheel run out. Easy and obvious to check, but the disk spider design already has appropriate compliance in that direction. It takes a specially made fixture to do a radial alignment check. No one seems to be doing this, and I have only sent my free rig to a couple of other riders. Of course i think the barrel shaft shape is due to differential hardness in the mating parts and the need for wear to be conjugal. Even other obvious competent high level mechanics disagreed with me (not you though - THX). FWIW I've only seen this failure on a couple of R1100 bikes, and never on any R1150s etc. My experience is very limited but from work I had access to a couple of gear/spline gurus (one now dead, and one from Russia!). They immediately confirmed radial misalignment.

I too been suspicious of the housing accuracy. This too is impossible to check as a loose part and it may simply be different details in the original machining setup as the raw casting distorts differently depending on how much Fritz torques the hold-down fixture. Day shift-nite shift problems? Who knows but BMW never got to the bottom of it.

Maybe there is more than one problem source? And maybe once the crankshaft rear main bearing is worn that future failures are inevitable.

I agree the clutch push rod should not be used for preliminary alignment of the engine and transmission. Thas should be done with 8 mm guide studs. It should only be slipped in and used to release the clutch during final pull up. Again i am reaching for straws here.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/04/17 11:12 PM

Originally Posted by nrp
Afternoon D.R. -

You are on the right track on this problem and I appreciate that someone understands what I have been bitching about for the last maybe 6 years..

I don't think BMW technicians ever figured out the spline wear problem. Somewhere in the management of all this warranty and service problem, there has been a high level assumption made that no one at lower levels really thought about and defended the problem and its source to management. And this is why the design approach was radically revised As an example, the number of posted theories and red herrings that have come up on this issue over the last 15 years suggest that it is not a simple deal. One that seems to be missed by many is the barrel shaped wear pattern that is said is due to flywheel run out. Easy and obvious to check, but the disk spider design already has appropriate compliance in that direction. It takes a specially made fixture to do a radial alignment check. No one seems to be doing this, and I have only sent my free rig to a couple of other riders. Of course i think the barrel shaft shape is due to differential hardness in the mating parts and the need for wear to be conjugal. Even other obvious competent high level mechanics disagreed with me (not you though - THX). FWIW I've only seen this failure on a couple of R1100 bikes, and never on any R1150s etc. My experience is very limited but from work I had access to a couple of gear/spline gurus (one now dead, and one from Russia!). They immediately confirmed radial misalignment.

I too been suspicious of the housing accuracy. This too is impossible to check as a loose part and it may simply be different details in the original machining setup as the raw casting distorts differently depending on how much Fritz torques the hold-down fixture. Day shift-nite shift problems? Who knows but BMW never got to the bottom of it.

Maybe there is more than one problem source? And maybe once the crankshaft rear main bearing is worn that future failures are inevitable.

I agree the clutch push rod should not be used for preliminary alignment of the engine and transmission. Thas should be done with 8 mm guide studs. It should only be slipped in and used to release the clutch during final pull up. Again i am reaching for straws here.


Evening NRP

Yes, definitely lots of speculation on the spline wear issue with some holding credibility & some really reaching for the stars.

Working for a major auto company I just can't believe that BMW didn't try to find the root on this as soon as warranty claims started piling up. My firm belief is that BMW qualified all the parts involved & set up spot quality checks on those parts as well going over the assembly process & fixturing pretty quickly.

I'm not saying that BMW didn't have a run of out-of-spec parts but no way do I believe that they didn't get a handle on that area pretty darn quick.

One thing that I keep thinking about is maybe the problem wasn't happening at original parts machining, or parts handling, or even at original build assembly. (that part of the failure chain would very easy for BMW to isolate & correct quickly)

An old dealer tec friend of mine had a theory that sort of holds water (at least in my mind)-- He claims he vaguely remembers uncrating the BMW 1150 era bikes & that they were shipped with no front wheel installed (this I know for a fact). His remembering is there were wood chalks or cribbing under the chassis in the rear of engine transmission area with the bike strapped down pretty tight.

These bikes were mainly shipped by ship so a dropped shipping crate with a motorcycle inside would hit the deck, or ground, or ??? pretty darn hard. His though is that due to the chalking or cribbing under the bike that a dropped crate could bend the front trans housing enough to cause a misalignment problem. (as I'm sure you know it doesn't take much input shaft misalignment to cause the basic spline joint to work as a gear-set instead of a spline coupling). He "thinks" that BMW changed the shipping crate strap down & under-bike support area on the later BMW 1150 bikes.

I do know that I saw a BMW tec/porter/whatever drop a motorcycle crate with a 1200RT inside about 4' when he was unloading it off a delivery truck with a small fork lift.

My friend was a pretty sharp tec but unfortunately he says uncrating bikes was not something he regularly did, or did often.

It's a credible theory anyhow as well as possibly explaining why it might have taken BMW a l-o-o-o-n-g time to identify.

I have heard (no confirmation though) that European 1150 bikes had a lot less spline failures. If this is true then most were probably not shipped by ship or stacked 10 crates high so it could fit the above theory I suppose.

Just another random theory tossed in the ring, eh?
Posted By: Alan Sykes

Re: R1150r rockster spline/gearbox integrity - 12/07/17 02:17 PM

Wow !

Good ole Dirt Rider now seems now to have come up with a logical explanation as to why :-

a) it was only a set number of 1150 bikes that exhibited premature spline wear. And

b) far fewer 'local market' bikes ever had the problem.

It's because of crate-drops during shipping by sea to overseas markets !

A bike that had been heavily dropped prior to delivery was likely to be bent out-of-true at the crucial point - and bikes delivered to EU customers from Berlin are delivered by BMW's own sub-contracted trucker, Aichinger GmbH, and thus are less likely to have been dropped sufficiently hard to cause the damage.

On the ADV Rider forum, in the ancient thread that discusses this topic at the most detailed length, which I've studied in detail for days in the past, there is an astonishing total of thirty-plus pages, and none of the experts expounding their theories has ever considered this shipping / crate-dropping possibility. DR - I bet your pal is spot-on with his !

My inside contact on the shop-floor in Berlin, a team-leader called Helmut who's now retired, was always quite circumspect about the possibility of premature spline wear being caused by an assembly-monkey or machining-robot fault involving mis-placed dowels on the rim of the bell-housing. He only ever begrudgingly allowed the possibility on the few occasions whenever we chatted about it in a Berlin Stube over jugs of ale.

V-e-r-y
I-n-t-e-r-e-s-t-i-n-g.

https://www.youtube.com/watch?v=krD4hdGvGHM

AL in s.e. Spain
Posted By: sardineone

Re: R1150r rockster spline/gearbox integrity - 12/07/17 04:02 PM

You said VERY................Interesting! I would have used a linked image, but they are getting a bit troublesome so I have it attached. grin

Alan I just noticed you are posting from Spain. My attached photo is from a skit on a popular American TV show Rowan & Martin's Laugh-In that used the quote "very interesting" from 1968 to 1973. Very Interesting

Attached File
artejohnson-interesting.jpg  (10 downloads)
Posted By: AndyS

Re: R1150r rockster spline/gearbox integrity - 12/07/17 04:13 PM

...but stupid.
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/07/17 05:06 PM

Although shipping damage is a VERY real possibility, I only have had direct experience w two R1100RT bikes. FWIW I recall they both were out of alignment in the same direction, with the transmission axis up and slightly to the right of the engine center line.. Were R1100s crated the same way? The weaker clutch housing design of the Oilheads would also make them more susceptible to shipping hazards,

I also have had a spline strip out on my 1975 R90/6 Airhead at less than 30K miles. Even if it had been dropped, the robustness of the clutch housing would seem to only allow a machining error, which I know still exist in it.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/07/17 06:33 PM

Originally Posted by nrp
Although shipping damage is a VERY real possibility, I only have had direct experience w two R1100RT bikes. FWIW I recall they both were out of alignment in the same direction, with the transmission axis up and slightly to the right of the engine center line.. Were R1100s crated the same way? The weaker clutch housing design of the Oilheads would also make them more susceptible to shipping hazards,

I also have had a spline strip out on my 1975 R90/6 Airhead at less than 30K miles. Even if it had been dropped, the robustness of the clutch housing would seem to only allow a machining error, which I know still exist in it.


Afternoon NRP

Your airhead spline issue was possibility because the trans wasn't allowed to center on the crankshaft (back in the airhead days we would run the engine with the trans bolts very slightly loose then operate the clutch lever a few times during the process as that would allow the trans to center up on the spinning & self-centering clutch disk, then we would snug the trans bolts up before shutting engine down) -- Not sure it was "THE" cure but doing this really cut down or eliminated return spline failures.

Something I had thought about doing on the oilheads but never have, as it would also take loose fitting (or removed) alignment dowels to work.
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/07/17 11:28 PM

Originally Posted by dirtrider
Originally Posted by nrp
Although shipping damage is a VERY real possibility, I only have had direct experience w two R1100RT bikes. FWIW I recall they both were out of alignment in the same direction, with the transmission axis up and slightly to the right of the engine center line.. Were R1100s crated the same way? The weaker clutch housing design of the Oilheads would also make them more susceptible to shipping hazards,

I also have had a spline strip out on my 1975 R90/6 Airhead at less than 30K miles. Even if it had been dropped, the robustness of the clutch housing would seem to only allow a machining error, which I know still exist in it.


Afternoon NRP

Your airhead spline issue was possibility because the trans wasn't allowed to center on the crankshaft (back in the airhead days we would run the engine with the trans bolts very slightly loose then operate the clutch lever a few times during the process as that would allow the trans to center up on the spinning & self-centering clutch disk, then we would snug the trans bolts up before shutting engine down) -- Not sure it was "THE" cure but doing this really cut down or eliminated return spline failures.

Something I had thought about doing on the oilheads but never have, as it would also take loose fitting (or removed) alignment dowels to work.

I tried that at the recent spline lube on my R90/6 but there was no combination of re-clutching with loose bolts that reduced the breathing between the transmission and the engine. I couldn't come up with anything to measure the error since it is a really blind assembly.

Of course I did not do that on the previous disassembly on the spline strip out as I didn't know a lot about the nature this failure back then in pre-Internet forum days. I do remember though that the input shaft front bearing was also shelled out probably from excessive radial loading.

You (and anyone for that matter) are welcome to use my fixture for checking Oilhead engine-transmission alignment. It requires the guts to be taken out of the transmission but the measurement can then be made in a few minutes, and includes the indicator. It travels well thru the US post office for only the cost of postage. I also have raw material and a setup to make fairly precise offset alignment pins on my old lathe once the measurement has been made.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/07/17 11:50 PM

Evening NRP

I tried that at the recent spline lube on my R90/6 but there was no combination of re-clutching with loose bolts that reduced the breathing between the transmission and the engine. I couldn't come up with anything to measure the error since it is a really blind assembly. Yes, they will still move around a little but I can usually make them much better. The trick is to have the bolts j-u-s-t loose enough to allow centering but not a lot of breathing shake. Any chance that you have a worn rear main bearing in that bike?

Of course I did not do that on the previous disassembly on the spline strip out as I didn't know a lot about the nature this failure back then in pre-Internet forum days. I do remember though that the input shaft front bearing was also shelled out probably from excessive radial loading. I have seen a number of front bearings trashed when spline damage is present.

You (and anyone for that matter) are welcome to use my fixture for checking Oilhead engine-transmission alignment. It requires the guts to be taken out of the transmission but the measurement can then be made in a few minutes, and includes the indicator. It travels well thru the US post office for only the cost of postage. I also have raw material and a setup to make fairly precise offset alignment pins on my old lathe once the measurement has been made. Thanks for the offer but I have my own as I check every 1150 that I work on for stripped splines (haven't done one I quite a while now though). I have a 4 jaw chuck for my lathe so making offset dowels is fairly easy, just a pain to adjust them to eliminate the run out.


[/quote]
Posted By: Mark C

Re: R1150r rockster spline/gearbox integrity - 12/08/17 01:53 AM

I know the relationship between the transmission and clutch plate are fixed, once installed, but doesn't the clutch plate spin every time it's dis-engaged, grabbing a different location on the pressure plates each time?
I also know BMW tells you to never use the mounting bolts to pull the transmission into clutch assembly, but I feel it's not a direct fit sometimes when the locators are dictating position and may pull splines over and away each time you pull in clutch.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/08/17 01:02 PM

Morning Mark C

I know the relationship between the transmission and clutch plate are fixed, once installed, but doesn't the clutch plate spin every time it's dis-engaged, grabbing a different location on the pressure plates each time?--Yes, the clutch disk changes it's clocking to the crankshaft every time the clutch is disengaged but it never changes it's clocking on the transmission splines.


I also know BMW tells you to never use the mounting bolts to pull the transmission into clutch assembly, but I feel it's not a direct fit sometimes when the locators are dictating position and may pull splines over and away each time you pull in clutch.--Actually, with a mis-aligned trans it pulls the clutch (disk) over & away from the transmission input shaft instant center with the clutch engaged & spinning. (With it disengaged it allows the disk to re-center on the trans splines/ then with it engaged it allows the disk to re-center on the spinning crankshaft center). If the two aren't the very same you then get spline wear.

Due to the spinning crankshaft & spinning clutch housing the clutch disk tends to re-center itself on the spinning crankshaft center when re-engaged so it runs down the road with clutch disk centered on the crankshaft but puts a side load or bending load on the trans input shaft & splines.

This side load "or bending load" on the spline joint (due to misalignment) isn't a big problem for a short while, as long as the spline joint is very tight, as it still acts & transfers torque as a basic spline coupling (it just deflects the clutch hub & trans input shaft). But over time the off-set or misalignment causes a little spline wear & ONCE the spline joint gets a little wear or slop in it, it starts acting more like a gear-set than a spline joint due to the misalignment. Once it starts acting as a gear-set it will then wear out quickly from then on unless it is kept continually lubricated (not just lubricated every few thousand miles but continually).

The true fix or (repair) is to purposely & with precision center the transmission's spinning input shaft instant center on the spinning crankshaft's instant center with absolutely no offset or angular mating. The offset is pretty easy to find (using a dial indicator mounted on the crankshaft & sweeping the trans front cover bearing hole) & not too difficult to repair (using offset alignment pins), but the angular mating is very difficult to find & even if identified it is very difficult to re-machine the trans to engine mating area to correct it.
Posted By: Alan Sykes

Re: R1150r rockster spline/gearbox integrity - 12/08/17 02:30 PM

DirtRider - is this why Moto Guzzi designed their version of the same single-plate dry clutch to include a thrust bearing at the 'other' end in order to keep everything in line ?
AL
Posted By: Mark C

Re: R1150r rockster spline/gearbox integrity - 12/08/17 02:54 PM

Thanks for response DR,
Concluding offset pins for a repair should never be anyone's problem, but the manufacturer.
Like I said, what does BMW call the plastic transmission cover used on Hexheads?
I call it an inspection cover, so at least it is possible to see the fit after installation.
To the best of my knowlefge (LIMITED) BMW has never addressed or accepted any responsibility (financial) as a major drive train problem.
From what I've heard, BMW denies claims as owner abuse for a warranty request?
I may be wrong but auto manufacturers used bell housings way back and BMW decided to combine it with the transmission.
Probably a cost only consideration. So much for over engineering?
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/08/17 03:22 PM

Originally Posted by Alan Sykes
DirtRider - is this why Moto Guzzi designed their version of the same single-plate dry clutch to include a thrust bearing at the 'other' end in order to keep everything in line ?
AL


Morning Al

You would have to ask Guzzi design & engineering.

That isn't a thrust bearing but more like a pilot bearing--In any case a lot of rear wheel drive vehicles use a pilot bushing or bearing on the front of a longer input shaft. They work great on long input shafts but don't work good on short stubby input shafts or on input shafts that have a long shaft overhang rearward of the front input shaft bearing. You just can't effectively use a pilot bearing on a one piece full length input shaft as that requires all 3 bearings be in perfect alignment (possible but not feasible in a production built assembly).

To have a front pilot bearing there needs to be enough real-estate in the clutch housing to allow either a throw-out bearing there or a throw-out fork there as a rear mounted slave cylinder or pass-through push rod isn't then possible.

As to why BMW used the system they did? You would have to ask them but from my prospective (auto engineering background) the current BMW system or rear mounted slave cylinder & pass-through push rod allows a much shorter transmission therefor a longer rear swing arm & better rear suspension dynamics.

There is absolutely nothing wrong with the BMW rear slave & pushrod clutch operating system (design & function wise) as long as the product ends up in the hands of the customer with everything built to design & it was designed properly.
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/08/17 03:51 PM

Morning Mark C

Concluding offset pins for a repair should never be anyone's problem, but the manufacturer. --True, but BMW isn't the only motor company that has needed to address input shaft alignment issues (look at Chrysler back in the 60's). If the trans to engine mating area is designed properly then built to those designs it should not ever need any sort of alignment check or altering. But that is story book fantasies, real life tends to not always work out as planned.

Like I said, what does BMW call the plastic transmission cover used on Hexheads? --It's called a clutch cover.


I call it an inspection cover, so at least it is possible to see the fit after installation.--I guess it could be called anything that you want but I seriously question what can be inspected through that cover (alignment wise). I guess, eventually it could be used to check for spline wear but it is easier to just do that through the starter hole & there seems to be little need for that on the 1200 bikes.


To the best of my knowledge (LIMITED) BMW has never addressed or accepted any responsibility (financial) as a major drive train problem.
--AFSIK BMW has addressed spline wear on some bikes for some customers. I do (personally) know (2) 1150 riders that had BMW repair their bikes for a spline issue under a good-will or whatever you want to call it. This usually depends on the dealer involvement, owner (ie original owner), etc. __BUT! even though the bikes were repaired by BMW the root failure issue wasn't addressed so both bikes re-failed at a later time.

But you are correct (AFAIK) that BMW hasn't come right out & said they have spline failure problems. But they haven't admitted much of anything on ANY re-occurring failures unless forced to.

From what I've heard, BMW denies claims as owner abuse for a warranty request?--Possible, but this is where the dealer steps in & works with BMW to remedy the problem for the customer.

I may be wrong but auto manufacturers used bell housings way back and BMW decided to combine it with the transmission.
Probably a cost only consideration. So much for over engineering?
-- There is no real (standalone) bell housing as that is not needed (the trans front cover is the combination front cover & clutch (bell) housing. Again we have the length issue to deal with. Make the clutch housing a separate part then either the bike gets longer, the engine shorter, or rear swing arm shorter (or all of the above). LOTS of current automobiles & light trucks don't use a stand alone clutch housing (bell housing) & there doesn't seem to be many issues in that area. About the ONLY real advantage to using a standalone clutch (bell) housing is it allows different materials to be used for the housing & the transmission (most are all the same alloy now).
Posted By: Cap

Re: R1150r rockster spline/gearbox integrity - 12/09/17 07:32 PM

Originally Posted by Mark C
To the best of my knowledge (LIMITED) BMW has never addressed or accepted any responsibility (financial) as a major drive train problem


I had a 2001 R1150GS that I bought new from a dealer in Denver. And after about 2 years, I noticed oil seeping from a spot on the seam between the engine and the transmission. I took it to my local BMW dealer in Fort Collins, not the one from which I bought the bike but the one that had done all the service to that point. And I asked, "what is that?"

With that prompting, they took the whole bike apart, noted an almost stripped trans input shaft, and found the source of a small oil leak (they were vague, but I think it was a small crack in the engine block). They installed a new transmission and clutch, and repaired the crack (weld?), and refreshed my factory warranty for an additional year. I was somewhat impressed, given that I was expecting that I would need to argue with them about it. No charge.

So, this is a sample of 1, but at least in my case, BMW backed their product.

Cap
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/09/17 08:22 PM

The oil leak was probably from the rear engine crankshaft seal, and the crankshaft rear main bearing was probably worn from the alignment-induced spline side load. It comes really down to where was the exact leak source. Was that why they were vague about the leakage?
Posted By: Craig G.

Re: R1150r rockster spline/gearbox integrity - 12/09/17 10:22 PM

Does anyone know, first hand, of a bike that failed a spline relatively early in life (~30k miles), was repaired and did not have another failure... period? If so do you know what the repair consisted of?
Posted By: dirtrider

Re: R1150r rockster spline/gearbox integrity - 12/09/17 11:26 PM

Originally Posted by Craig G.
Does anyone know, first hand, of a bike that failed a spline relatively early in life (~30k miles), was repaired and did not have another failure... period? If so do you know what the repair consisted of?


Evening Craig G

I can't give you the period but I did a spline repair on a 28,xxx 1150RT around 2008 that didn't have another spline failure while the owner still owned it. At around 62k he sold it (traded it) then lost track of it.

All I did on that bike was install a new input shaft, new clutch disk, new slave cylinder, & some seals, then use offset dowels to align the trans front cover to the crankshaft.

I have done a few over the years but they get sold & passed on to new owners so keeping track of them is impossible.
Posted By: Jim Moore

Re: R1150r rockster spline/gearbox integrity - 12/10/17 11:01 AM

I installed a known-good used transmission an R1100S. It fixed the problem. You can find them for a few hundred bucks on eBay. Make sure you get some close-ups of the splines.
Posted By: Cap

Re: R1150r rockster spline/gearbox integrity - 12/10/17 07:37 PM

Originally Posted by nrp
The oil leak was probably from the rear engine crankshaft seal, and the crankshaft rear main bearing was probably worn from the alignment-induced spline side load. It comes really down to where was the exact leak source. Was that why they were vague about the leakage?


I really don't know where the oil was leaking... I asked the dealer for an explanation, and they confirmed that it was engine oil. My recollection is hazy, but I think they mentioned a crack. I found that somewhat alarming, especially when they would not explain the way they fixed it, other that to assure me that they were confident that they had fixed it permanently. Given that they had just placed a new transmission and clutch on the bike, at no charge, I was reluctant to press the issue.

You might be right that the oil was leaking from the rear main seal. Can those be replaced without dismantling the engine? Maybe it was the seal that was cracked. In any case, the bike ran fine (or at least as well as it ever had, which for a 2001 1150 meant that it surged badly and burned a quart of oil every 1000 miles). I rode it long enough to verify that it seemed OK, then sold it with a complete history and the remaining warranty. Never heard a complaint from the next owner.

As an aside, my 2004 R1150RT does not burn oil, and does not surge as long as both stick coils are working.

Cap
Posted By: nrp

Re: R1150r rockster spline/gearbox integrity - 12/11/17 02:29 AM

It would be hard to evaluate the radial alignment if a freshly assembled (with new parts) engine-transmission system. The only possibility might be if the tangential clearance as monitored on the clutch disk outside diameter could be verified for clearance. With new parts (shaft and clutch disk hub) I'd guess the tangential backlash at the OD would be maybe 1/32 inch. Actually, anyone checking a rebuild situation should probably look at this on reassembly through the starter port. If there is no backlash, it suggests that there is no spline tooth clearance and that it is all used up by assembly alignment error.and binding

The real number is that the radial misalignment according to some DIN (German Industrial Norms) specs I recall seeing is about .003 inch max. For a spline of this size, speed, and torque environment that seems more than a little too much.
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