BMWSportTouring BMWST DB
Previous Thread
Next Thread
Print Thread
Page 3 of 4 1 2 3 4
#1002062 - 12/07/17 04:13 PM Re: R1150r rockster spline/gearbox integrity [Re: eliastfk93]  
Joined: Nov 2002
Posts: 4,781
AndyS Offline
Member
AndyS  Offline
Member

Joined: Nov 2002
Posts: 4,781
Somerset, Great Britain.
...but stupid.

#1002065 - 12/07/17 05:06 PM Re: R1150r rockster spline/gearbox integrity [Re: eliastfk93]  
Joined: Dec 2004
Posts: 753
nrp Offline
Member
nrp  Offline
Member

Joined: Dec 2004
Posts: 753
Minnetonka MN
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.

#1002068 - 12/07/17 06:33 PM Re: R1150r rockster spline/gearbox integrity [Re: nrp]  
Joined: Jun 2010
Posts: 13,261
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,261
Ohio
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.


D.R. ___
Sent from my rotory dial wall phone!
#1002079 - 12/07/17 11:28 PM Re: R1150r rockster spline/gearbox integrity [Re: dirtrider]  
Joined: Dec 2004
Posts: 753
nrp Offline
Member
nrp  Offline
Member

Joined: Dec 2004
Posts: 753
Minnetonka MN
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.

#1002080 - 12/07/17 11:50 PM Re: R1150r rockster spline/gearbox integrity [Re: nrp]  
Joined: Jun 2010
Posts: 13,261
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,261
Ohio
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]


D.R. ___
Sent from my rotory dial wall phone!
#1002086 - 12/08/17 01:53 AM Re: R1150r rockster spline/gearbox integrity [Re: dirtrider]  
Joined: Oct 2004
Posts: 133
Mark C Offline
Member
Mark C  Offline
Member

Joined: Oct 2004
Posts: 133
norcal
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.

#1002094 - 12/08/17 01:02 PM Re: R1150r rockster spline/gearbox integrity [Re: Mark C]  
Joined: Jun 2010
Posts: 13,261
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,261
Ohio
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.


D.R. ___
Sent from my rotory dial wall phone!
#1002103 - 12/08/17 02:30 PM Re: R1150r rockster spline/gearbox integrity [Re: eliastfk93]  
Joined: Aug 2014
Posts: 86
Alan Sykes Offline
Member
Alan Sykes  Offline
Member

Joined: Aug 2014
Posts: 86
Almeria, Spain
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


This is a list of the people I'd trust with my bike
#1002106 - 12/08/17 02:54 PM Re: R1150r rockster spline/gearbox integrity [Re: dirtrider]  
Joined: Oct 2004
Posts: 133
Mark C Offline
Member
Mark C  Offline
Member

Joined: Oct 2004
Posts: 133
norcal
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?

#1002108 - 12/08/17 03:22 PM Re: R1150r rockster spline/gearbox integrity [Re: Alan Sykes]  
Joined: Jun 2010
Posts: 13,261
dirtrider Offline
The Oracle
dirtrider  Offline
The Oracle
Member

Joined: Jun 2010
Posts: 13,261
Ohio
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.


D.R. ___
Sent from my rotory dial wall phone!
Page 3 of 4 1 2 3 4

Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.029s Queries: 15 (0.020s) Memory: 2.8118 MB (Peak: 2.9999 MB) Zlib enabled. Server Time: 2017-12-13 12:59:24 UTC