Transmission input shaft spline lubrication

[kalali]

Read a lot about folks having issues with the input shaft drying out and causing excessive spline wear, etc. I also understand this is less of an issue with the 5-speed bikes but still an important maintenance item. So with all that been said, I have two questions: Is this a mileage dependent or age dependent maintenance task? Is there a way to "visually" inspect the shaft splines in order to assess its condition? What are the symptoms of worn input shaft splines? I have a 16 year old bike but with only 17K miles and plan to keep it for a long time and would like to decide whether or not I should proactively take on lubing the splines to avoid any future issues. Finally, what would be fair number of labor hours if I decide to have a shop do it for me. Thanks.

[AndyS]

Hi Kalali.

You have a few things wrong here.

Most of the problems with the gearbox input splines were on the early 1150 series up to 2003.

 

The issue is not about splines drying out, it is about mis-alignment between the gearbox and the engine.

However lubrication within reason is never a bad thing.

 

Part of the spline action can be checked (and lube carried out at the same time).

 

Have the bike on the centre stand.

The method is to remove the starter motor, then put the bike in gear and whilst jogging the back wheel forward and back, view into the starter housing with a really good torch (flash light).

 

You are looking at the input shaft and seeing if the shaft turns at all WITHOUT rotating the clutch housing. If the shaft but the housing doesn't, you should be suspicious of an issue.

 

As for lubing, then this is what I do.

Make up a mixture of Molybdenum Disulphide powder and IPA (Isopropyl alcohol) the mixture needs to be runny.

Then using a fine artists brush on a stick, carefully brush som of this mixture on the uppermost spline. work the back wheel so that you can repeat the proceedure on spline at a time and repeate until it has all been coated at least once.

Take care not to allow the mixture to migrate down onto the clutch plate.

 

[greiffster]

Have the bike on the centre stand.

The method is to remove the starter motor, then put the bike in gear and whilst jogging the back wheel forward and back, view into the starter housing with a really good torch (flash light).

 

You are looking at the input shaft and seeing if the shaft turns at all WITHOUT rotating the clutch housing. If the shaft but the housing doesn't, you should be suspicious of an issue.

 

I use a zip tie to hold in the clutch lever while inspecting.

[kalali]

Thank you both for your input. I was aware of the issue around the input shaft splines not completely seated inside the clutch hub/carrier in the 6-speed bikes causing excessive wear but misunderstood the role the lube played in the wear. I saw a video where the entire transmission and clutch was removed in order to lube the splines and am pleasantly surprised to hear that you could apply the lubricant without going that process. Thanks again.

[Birdman40205]

I thought it was all bikes of the oilhead era. How would misalignment happen? From the factory, or inept shop work? Very nice to know I can check mine. My 94 RS got a clutch about 500 miles before I got it, and the shop is known to be a good one, so I am hoping lube and proper alignment happened.

[PAS]

I can't imagine much of the lube getting into the area that needs it doing that technique.

[JamesW]

I can't imagine much of the lube getting into the area that needs it doing that technique.

 

I would 100% agree. If you want to lube your splines separate the trans from the engine clean and inspect and then lube the splines. If it's worth doing do it right, simple as that. Now, you can argue the need to do anything, your choice.

[AndyS]

Have you tried it?

It shouldn't really need doing. After all, you never strip a car apart to do it on do you?

 

Anyhow, do you have a transmission lying around that you can take a look at. If so give it a go. you will be impressed with the results.

Molybdenum disulfide (MoS2) with a very mobile carrier such as IPA, wicks incredibly well. Like I say, put it on the upper spline and then rock the transmission and it walks along that spline and on to the mating surfaces really well. Do each spline and repeat the same process.

By all means strip the bike apart if you want to - thats your choice.

 

Once the IPA has evaporated off it leaves a lovely thin film of MOS2 (which, frankly, is as good as a big dollop of the stuff.

 

If there is misalignment, then no amount of 'greasy goop' is going to save it.

 

Birdman40205, the misalignment was from the factory and only really effected a smallish era of the Oilhead bikes.

[Jim Moore]

I thought it was all bikes of the oilhead era. How would misalignment happen? From the factory, or inept shop work? Very nice to know I can check mine. My 94 RS got a clutch about 500 miles before I got it, and the shop is known to be a good one, so I am hoping lube and proper alignment happened.

 

It is / was a somewhat common occurrence on bikes with the six-speed transmission. I've heard of it happening on a five speed bike, but it's rare. Like unicorn-rare. l

[kalali]

 

This might help answering some of the questions. It did for me.

 

[Birdman40205]

It is / was a somewhat common occurrence on bikes with the six-speed transmission. I've heard of it happening on a five speed bike, but it's rare. Like unicorn-rare. l

 

Mine is a 5'r. Hopefully not the elusive unicorn

I can see why they went to a 6'r, but I have no complaints. I keep riding it because I know as soon as the salt and cinder trucks lay down their gravelly horror, the season will be over. So now, I have a list of things to do. BAS screw clean, starter R&Clean, check splines out.

[kalali]

Ironically, the fact that you even see any exposed portion of the splines is exactly why they fail prematurely. Ideally, the length of the splines on the shaft should be at least equal to the depth of the mating splines on the clutch plate.

Watch the video I posted. Couldn't explain it any better.

[Stan Walker]

It's a theory. No more proven than any other.

It doesn't explain why my 02 RT hasn't failed at 134,000 miles

I fit his profile. 1150 Oilhead. Riden gently. Redline is a foreign concept to me. Almost all my riding is done below 4000 RPM. I often up shift by 3500 RPM. The exception is when riding Interstates, which I try to avoid. I prefer little 2 lane back country roads and will often add time to a trip to enjoy them.

[Birdman40205]

IRedline is a foreign concept to me. Almost all my riding is done below 4000 RPM. I often up shift by 3500 RPM. The exception is when riding Interstates, which I try to avoid. I prefer little 2 lane back country roads and will often add time to a trip to enjoy them.

 

This is exactly the way I ride. I dont think my bike has seen 4k rpms yet. In 5th, I am doing 80 at 3000+ rpm, so really no reason to go beyond that, When I got the bike, I flipped with every "Thump" the trans would make. Already a chunky box and aware of the trans issues, I thought it was imploding with every strange noise. Now that I have learned the bike better, I can shift it very smoothly by not rolling off the gas when I shift. Its seemless, and no clunkage, for want of a better term. But I have to ask myself, why did I gravitate to a bike that has pages of google on trans problems??

[Shane J.]

https://dl.dropboxusercontent.com/u/51922644/2015-10-11%2018.32.12.jpg

https://dl.dropboxusercontent.com/u/51922644/2015-10-11%2018.32.37.jpg

 

I can't seem to figure out how to add the actual images (maybe someone can do it for me), click on them to view. One shows my recently replaced transmission with the worn input shaft, the other is the clutch disc. As you can see, the clutch disc was the weak link here. It was only a matter of time until the input shaft followed along. I was going to add the extender to my new clutch plate but after seeing this I don't think that last little bit of splines would last any longer than the rest of it.

 

back to homemade pizza and beer for thanksgiving (traditional NW fare) then a ride

[kalali]

To those of you who watched the video I posted, are you debating the fact that the shaft does not fully seat inside the clutch hub? Obviously not very bike will run into this issue but you can't argue the facts.

[legarem]

I've done complete spline lubing at 75000 kms. There was no wear and clutch disk was good. Next time, when I will have to change the clutch, i'll go with this kit.

 

http://advrider.com/index.php?threads/bmw-1150gs-clutch-splines-spacer-kit.964425/

[nrp]

To those of you who watched the video I posted, are you debating the fact that the shaft does not fully seat inside the clutch hub? Obviously not very bike will run into this issue but you can't argue the facts.

What facts do you need to explain that some bikes wear the splines and some do not? Splines are widely used to transmit torques from one element to another - and some are even sliding. What's unique here is that we are only working with assembly lube, and life depends on alignment.

 

Those that wear the splines have demonstrated alignment errors when an accuratee measurement rig is used. They also show severe wear of the rear crankshaft main bearing in a corresponding direction, again for those people that have looked for it.

 

And it is not only the 1150s that do it. My R90/6 did it at about 20K and I personally worked on a R1100 that stripped out. My R90 still has an alignment error as I can feel it wiggling when the engine-transmission bolts are loosened slightly.

 

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

[roger 04 rt]

...

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

 

What is the basis for your statement above that spline engagement is not a factor?

[Jim Moore]

IRedline is a foreign concept to me. Almost all my riding is done below 4000 RPM. I often up shift by 3500 RPM. The exception is when riding Interstates, which I try to avoid. I prefer little 2 lane back country roads and will often add time to a trip to enjoy them.

 

This is exactly the way I ride. I dont think my bike has seen 4k rpms yet. In 5th, I am doing 80 at 3000+ rpm, so really no reason to go beyond that, When I got the bike, I flipped with every "Thump" the trans would make. Already a chunky box and aware of the trans issues, I thought it was imploding with every strange noise. Now that I have learned the bike better, I can shift it very smoothly by not rolling off the gas when I shift. Its seemless, and no clunkage, for want of a better term. But I have to ask myself, why did I gravitate to a bike that has pages of google on trans problems??

 

C'mon kids! Rev those engines.

[legarem]

C'mon kids! Rev those engines.

 

I had a Honda ST1100 and a Kaw Concours I loved to rev but with my 1150RT, this is another story like Stan and Birdman. Also, since I use a LC-1 to change the AFR setting, I discovered some low end grunt of this twin. These are not the funniest bikes to rev.

[Jim Moore]

C'mon kids! Rev those engines.

 

I had a Honda ST1100 and a Kaw Concours I loved to rev but with my 1150RT, this is another story like Stan and Birdman. Also, since I use a LC-1 to change the AFR setting, I discovered some low end grunt of this twin. These are not the funniest bikes to rev.

 

No, really. They are.

[kalali]

To those of you who watched the video I posted, are you debating the fact that the shaft does not fully seat inside the clutch hub? Obviously not very bike will run into this issue but you can't argue the facts.

 

Those that wear the splines have demonstrated alignment errors when an accuratee measurement rig is used. They also show severe wear of the rear crankshaft main bearing in a corresponding direction, again for those people that have looked for it.

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

 

Please explain this (mis)alignment issue. Is this misalignment caused during original assembly and if so, is it due to mismatch tolerances?

[AndyS]

The quick answer is yes, it is a manufacturing issue. As to how, nobody REALLY knows. Also which exact bikes are affected is unknown, but the most common occurrences were in the 1150 single spark models. As Stan and many others will point out, it doesn't effect all bikes of that era either.

 

My advice is really don't worry about it, because unless you strip the bike down and have access to some very accurate measuring equipment you will be none the wiser.

 

There are plenty of threads on this if you want to bore yourself silly. The Oil threads are funnier though!

[kalali]

What are the obvious symptoms of this issue? I guess any play between the clutch hub and the shaft would be a good indication of some wear and that can be visually verified by removing the starter and turning the rear wheel in gear. I saw one video showing an R1150RT-P with only 17K miles where the rear wheel was spinning with the transmission in neutral on a center stand. It spun faster as more gas was applied. I'm guessing this was an extreme case given the mileage. The input shaft was noticeably worm when the bike was taken apart.

[dirtrider]

What are the obvious symptoms of this issue? I guess any play between the clutch hub and the shaft would be a good indication of some wear and that can be visually verified by removing the starter and turning the rear wheel in gear. I saw one video showing an R1150RT-P with only 17K miles where the rear wheel was spinning with the transmission in neutral on a center stand. It spun faster as more gas was applied. I'm guessing this was an extreme case given the mileage. The input shaft was noticeably worm when the bike was taken apart.

 

Morning Kalali

 

That rear wheel spinning with trans in neutral is normal due to gear oil drag between normally disconnected spinning parts inside the trans. (remove the gear oil, wash the trans insides out with parts cleaner & the rear wheel spinning with trans in neutral will go away)

 

Here is an old thread on spline wear that covers a LOT of ground on possible reasons & cures-

 

Spline Wear thread, click here

[Birdman40205]

I looked using a variety of meta-phrasing, but couldn't find anything, so I ask here: Is there a list or database of BMW mechanics who are recommended in each state, on this board? I imagine if this were to happen to someone, it is going to be a very high repair cost. It would be comforting to know that the person you are paying to do the repair has a history of successful repairs. I feel pretty comfortable doing a lot of work, but I think a clutch/shaft repair would be out of my envelope of skill.

[nrp]

...

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

 

What is the basis for your statement above that spline engagement is not a factor?

When someone finds a bike with a failed spline and no serious crankshaft rear main bearing wear. Otherwise I see these potential design and manufacturing issues:

 

1) The raw casting of the clutch housing is flimsy because it has no complete flange at the engine end (to accommodate the starter). It may be adequate when assembled but it could be sensitive to how it is mounted in any machining fixture during manufacture.

 

2) The alignment pins are very short given their diameter and could be cocking if someone uses them to drag everything into alignment on assembly.

 

3) The clutch disk should be kept fully disengaged during any pull up of the engine-transmission interface, lest the forces required to drag the clutch disk distort everything on pull up.

 

4) Lubrication - did they choose a poor grease?

 

There may be other reasons but BMW should have started with these.

[JamesW]

I do believe that the lack of full clutch disc hub engagement with the trans input shaft began around 1999. Up until that time the oilhead trans input shaft splines fully engaged with the clutch disc hub splines just like on all airhead models. I also think this lack of full engagement began with the introduction of the rather pointless hydraulic clutch around '99. I own a '93 1100 and an'04 1150 and have had both transmissions removed for spline cleaning and lubrication. I'll take the '93 over the 1150 any day.

[nrp]

My 2000 R1100RT had full spline engagement last time I looked.....

[roger 04 rt]

...

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

 

What is the basis for your statement above that spline engagement is not a factor?

When someone finds a bike with a failed spline and no serious crankshaft rear main bearing wear.

 

I don't understand how that criteria leads you to the conclusion that spline engagement is not a factor.

[JamesW]

My 2000 R1100RT had full spline engagement last time I looked.....

 

I don't doubt that. All I know for sure is that the 6 speed trans don't have full spline engagement whereas the early 1100 trans did. Somewhere I read that the issue began with the hydraulic (P.O.S) clutch.

 

I inspected the splines on my '04 1150RT at 35K miles and they were perfect. My theory is that if you have a good transmission engine alignment then maybe full spline engagement is not as critical as it would on a machine without good alignment. Maybe this is why the early 1100 machines don't seem to have the issue as they have full engagement.

 

I'll bet BMW knows the answer. I also think quality control was compromised around '99. I read the wethead forum to see if maybe quality has improved and so far so good it would seem.

[nrp]

...

I think there are particular design features in the oilhead bikes that make them more prone to alignment issues. And they are not because of the mismatched spline engagement.

 

What is the basis for your statement above that spline engagement is not a factor?

When someone finds a bike with a failed spline and no serious crankshaft rear main bearing wear.

 

I don't understand how that criteria leads you to the conclusion that spline engagement is not a factor.

Isn't that obvious? Crank bearing wear simply hasn't been checked from most other strip outs. What would engagement have to do with radial loads being transmitted across the spline? What else can cause simultaneous spline and bearing wear except radial misalignment?

[nrp]

All I know for sure is that the 6 speed trans don't have full spline engagement whereas the early 1100 trans did.

 

I inspected the splines on my '04 1150RT at 35K miles and they were perfect. My theory is that if you have a good transmission engine alignment then maybe full spline engagement is not as critical as it would on a machine without good alignment. Maybe this is why the early 1100 machines don't seem to have the issue as they have full engagement.

 

Then how can I explain my experience w only an R1100 and an R90/6 (both striped out)? Both had full engagement.

[JamesW]

Well, you could say s__t just happens and in some cases you would be right or you might ask yourself questions about how you operate your motorcycles. I know that in the case of my 1150 I never hardly ever ride in 6th gear and in the case of my 1100 I spend most of the time in 4th gear. My '93 1100RS has an M93 transmission which has a bit higher gear ration than later units that being the M94 and M97 so riding in 4th gear makes sense and imo the 6th gear on later oilheads is useless. I have long been of the opinion that lugging along at 60 MPH in 6th gear could be detrimental in the case of an 1150. Roger will diagree with this theory others will agree. Me, I like 5th gear and 5K RPM all day long. I think it very odd you would have the same issue on an airhead and an 1100 oilhead. Wonder what answer BMW would give you? I can guess. You know an airhead loves high revs and will happily go coast to coast running at 5K+ RPM. On your airhead are you the original owner and how often did you remove the trans to inspect, clean and lubricate those splines? You are definetely in the minority when in comes to failure on an 1100 but again s__t do happen.

 

I know the reason to lube splines on an airhead is to prevent metal fretting as in corrosion. I don't know if the metalurgy of the splines on an 1100 is similar to an airhead or not. When I inspected the splines on my '93 1100 I noticed the similarity in appearance and cut to those on my '81 R100RT (sold ).

 

Oh, how many miles were on your bikes at time of failures?

[Clive Liddell]

Hi kalali,

The rear wheel turning in neutral on c/stand is normal and I would be concerned that my rear brake was binding if it did not spin. I would say it's due to "windage" and a bit of friction from all the gears turning on the shafts (with the dogs in neutral of course).

 

Apologies: DR I see you have already dealt with this. Not good to be watching Australia/New Zealand cricket match while replying to posts :<(

[Jim Moore]

Then how can I explain my experience w only an R1100 and an R90/6 (both striped out)? Both had full engagement.

 

what year 1100, out of curiosity? How many miles?

[roger 04 rt]

 

What is the basis for your statement above that spline engagement is not a factor?

When someone finds a bike with a failed spline and no serious crankshaft rear main bearing wear.

 

I don't understand how that criteria leads you to the conclusion that spline engagement is not a factor.

Isn't that obvious? Crank bearing wear simply hasn't been checked from most other strip outs. What would engagement have to do with radial loads being transmitted across the spline? What else can cause simultaneous spline and bearing wear except radial misalignment?

 

Here are my thoughts.

1) I am personally aware of two R1150s that had hub failure at about 30,000 miles.

2) On the first bike, Hub and input shaft were replaced. Failed again in another 30,000. Next repair was clutch pack, full insertion, and new shaft. No wear at 70K additional miles.

3) On the second bike, failure at about 30K miles. New shaft, hub and full insertion. No wear at 30K additional miles.

 

I know that radial misalignment will cause wear. I know that 100% of engines and transmissions are misaligned since nothing is perfect. What I don't know is:

1) How much misalignment can be tolerated.

2) How much insertion depth affects connection looseness. I know that the hub can move a lot more on the shaft with a very short insertion.

3) I know that connection looseness affects rate of wear.

[dirtrider]

Morning Roger

 

 

Here are (Roger's) thoughts.

 

 

I know that radial misalignment will cause wear. I know that 100% of engines and transmissions are misaligned since nothing is perfect. What I don't know is:

 

1) How much misalignment can be tolerated.---

On the accepted spline wear?-- BMW (in a service bulletin on the K bike) says-- even a slight misalignment (above .25mm) can lead to spline wear. That is BMW's opinion not mine as .25mm seems like a LOT of misalignment to me. None the less that is BMW's official stance.

 

2) How much insertion depth affects connection looseness. I know that the hub can move a lot more on the shaft with a very short insertion.--- I'm sure it has some effect but if it is a major influencing factor then why don't all 1150 6 speed splines fail before 50K. Some fail at under 30K & others go 100K+ with pristine looking splines.

 

3) I know that connection looseness affects rate of wear.--- I'm sure it does to some extent & I can see linear wear forming from radial play or sloop. (in my mind) -- what I don't see from connection looseness is the extreme angular spline tooth wear we are seeing on the BMW 1150 splines. That wear is from a basic misalignment not a loose connection.

[Mark C]

I agree with JamesW.

When my 2004 R1150RT (beautiful looking) failed w/42k, I bought a wrecked 99R1100RT w/42k and removed and replaced the entire front end, frame, forks , wheel fairing and it still looks like a 2004 R1150RT but is the old 5 speed 1100 and from engine back.

Kept my old registration and hope to get 125+k like my last 1100RS.

Took a couple of days work, about the same as replacing another transmission.

I have had dozens of these apart and lubrication seems a moot point, because I have seen bone dry splines not wearing out.

If the transmission is bolted onto engine, it's really hard to believe there is much you can do to move it around any amount that makes a difference.

I sometimes wonder if it's the engines manufactured after the 1150's came out that could be the source of problems?

Mark

[JamesW]

DR brings up a good point when he talks about the angular wear pattern that we see on worn input shaft splines. In the many pictures that have been posted showing this wear pattern it seems to me that virtually all of the pics that I have seen are of worn 1150 splines and not 1100 splines that have full engagement of the clutch hub. Maybe it's just because so few 1100's fail compared to 1150 failures. Or maybe my memory is just failing me a bit. It does seem to me that it would be more difficult to get that wear pattern with more spline / hub engagement. No doubt in my mind BMW knows the answers to these questions.

[roger 04 rt]

Morning Roger

 

 

Here are (Roger's) thoughts.

 

 

I know that radial misalignment will cause wear. I know that 100% of engines and transmissions are misaligned since nothing is perfect. What I don't know is:

 

1) How much misalignment can be tolerated.---

On the accepted spline wear?-- BMW (in a service bulletin on the K bike) says-- even a slight misalignment (above .25mm) can lead to spline wear. That is BMW's opinion not mine as .25mm seems like a LOT of misalignment to me. None the less that is BMW's official stance. Agreed, about 0.010" seems like a lot.

 

2) How much insertion depth affects connection looseness. I know that the hub can move a lot more on the shaft with a very short insertion.--- I'm sure it has some effect but if it is a major influencing factor then why don't all 1150 6 speed splines fail before 50K. Some fail at under 30K & others go 100K+ with pristine looking splines. Based on the two bikes that I have familiarity with, It's my opinion that radial misalignment is the root of the problem but that insertion depth plays a role as well. Neither of the two bikes were realigned.

 

3) I know that connection looseness affects rate of wear.--- I'm sure it does to some extent & I can see linear wear forming from radial play or sloop. (in my mind) -- what I don't see from connection looseness is the extreme angular spline tooth wear we are seeing on the BMW 1150 splines. That wear is from a basic misalignment not a loose connection. A thorough scholarly article I read made the point that connection looseness was an accelerating factor in the wear rate for radial misalignment. At some point I will try to find and post a link to the article.

 

Morning DR,

Thanks for those answers. I've added some follow on thoughts above in blue.

RB

[dirtrider]

Afternoon Roger

 

One point to consider in relation to a loose clutch hub to trans input shaft fit is: there were a number of very loose clutch disk to input spline matchups (or wear) on the BMW 1100 5 speed bikes. In fact it was a problem that BMW eventually had to address by offering a tighter-fit clutch disk PN/ 21212325352 (Special clutch driving plate) to address the clutch rattle in neutral.

 

Even with those loose clutch hub to input shaft matchups there were very very few BMW 1100 (5) speed input shaft spline failures.

 

But per you point-- I can see a loose clutch hub to input shaft allowing more /earlier wear in a bike with a basic misalignment problem.

 

Thing is: on a basic misaligned bike-- the wear soon makes the clutch hub to spline fit become very loose no matter how tight it was as built.

 

[kalali]

Is it possible to visually inspect the input shaft spline to clutch hub fitment by peeking through the starter/flywheel opening? Someone had mentioned earlier about applying some lubricant through to the splines using a brush so I'm assuming that at least a portion of the shaft is visible, so is the absence.

[dirtrider]

Is it possible to visually inspect the input shaft spline to clutch hub fitment by peeking through the starter/flywheel opening? Someone had mentioned earlier about applying some lubricant through to the splines using a brush so I'm assuming that at least a portion of the shaft is visible, so is the absence.

 

Afternoon Kalali

 

Yes & no--

 

You can see some of the spline area but you can't see the part of the spline area that is worn.

 

To see the worn area on the input shaft you would need to unbolt the trans & slide it rearwards.

 

About all you can do through the starter area is see how much radial play the clutch disk has on the input shaft. (that is a fair indicator of spline wear)

[nrp]

Is it possible to visually inspect the input shaft spline to clutch hub fitment by peeking through the starter/flywheel opening? Someone had mentioned earlier about applying some lubricant through to the splines using a brush so I'm assuming that at least a portion of the shaft is visible, so is the absence.

 

Afternoon Kalali

 

Yes & no--

 

You can see some of the spline area but you can't see the part of the spline area that is worn.

 

To see the worn area on the input shaft you would need to unbolt the trans & slide it rearwards.

 

About all you can do through the starter area is see how much radial play the clutch disk has on the input shaft. (that is a fair indicator of spline wear)

Don't you mean tangential play atthe disk OD?

[dirtrider]

Is it possible to visually inspect the input shaft spline to clutch hub fitment by peeking through the starter/flywheel opening? Someone had mentioned earlier about applying some lubricant through to the splines using a brush so I'm assuming that at least a portion of the shaft is visible, so is the absence.

 

Afternoon Kalali

 

Yes & no--

 

You can see some of the spline area but you can't see the part of the spline area that is worn.

 

To see the worn area on the input shaft you would need to unbolt the trans & slide it rearwards.

 

About all you can do through the starter area is see how much radial play the clutch disk has on the input shaft. (that is a fair indicator of spline wear)

Don't you mean tangential play atthe disk OD?

 

Evening NRP

 

I actually meant to write "rotational" play but my mind wasn't properly communicating with my fingers.

[nrp]

I like "rotational" even better too.

[nrp]

JamesW - I had only about 20K miles on my 1975 R90/6 when the spline stripped about 1990. Found they were rusty & dry. That was before forums so on my own, I replaced everything & lubed with nickel based Neva-Seize from work. I recall the front transmission bearing was bad too but didn't realize the failure connection to alignment. It now has about 50,000 miles and the Neva-Seize seems to remain in the spline. It was checked again a couple of years ago after all these revelations when I tried to run the engine with the engine-transmission bolts loosened. Despite repeated clutch disengagements in neutral, I was unable to get the relative wiggling between the engine and transmission to go away at all. Because it is a blind assembly on a full diameter pilot, I don't know any way to document the misalignment. I still have and drive that bike on occasion.

 

There was a period when BMW was using a grease that was inappropriate for spline use. I don't know if my bike was in that period.

 

I bought it new in 1975 and still have it. It has low compression cyl base gaskets and frankly at 77, I drive it like an old grandmother.

 

 

The second bike, a 2001 R1100RT with ~51K miles, was a twin cities local and disassembled in June 2011 when I became involved in it. That's when I made up the test rig as documented and pictured on this web site about that time. That's when I happened to also stumble onto rear main bearing wear although I did not document it. We did not try to make offset alignment pins either, just repair and reassemble. I don't know what has since happened to that one.

 

 

The third example was a R1150 owned by SpaffyPD at the Pelican parts website. Using Internet discussions only, I arranged for him to document the misalignment and the rear main bearing clearance despite his lack of machinery experience. He has since described it very well on that site. I made up some offset pins on my metal lathe and mailed them to him with installation instructions.

 

 

I guess the 4th example is my 2000 R1100RT (a bike for every mission) that I disassembled at 20K miles a few years ago to find the splines were pristine. Greased w Neva-Seize and reassembled. Now at only 27K miles.

 

 

FWIW, that's the extent of my BMW spline experience except that before retirement 13 years ago, I was a mechanical engineer for 40 years on among other things, several high speed rotational hydraulic and mechanical systems. Otherwise, I am not a M/C mechanic.

[JamesW]

Hi nrp, Thanks for that info, very informative. I guess I've just been lucky after 40 years on BMW bikes and never had spline problems.

 

On your R90/6 did you ride a lot on wet roads that had been heavily salted previously? Very glad Oregon does not use sodium chloride just sand.

 

I think there are several problems that can cause spline issues and mis-alignmenet may be one of them for sure. I also think that rider riding technique is also an issue and might even cause a rear main bearing issue. I'm refering to the effects of flat twin rocking couple and how it might effect the rear main especially if the bike is ridden at low RPM in the higher gears. lack of full spline clutch hub mating in the 1150 may also be a contributing factor. Then we have BMW itself and their business philosophy and on and on....

 

I'm hardly a mechanical engineer just a long time rider with what I hope is a bit of common sense. I do all of my own maintenance and in the case of my 1150RT it has never been in any shop other than my own since day one and that includes the first service at 600 miles. Now the bike has just over 50K miles and has perfect splines. In that 50K miles it has not spent even 100 miles in 6th gear. The '93 R1100RSL I bought 3 years ago with only 1 mile on the odometer and I did the first service. I also, before ever starting it for the first time, separated the trans from the engine and lubricated the splines with Honda moly and Sig 3000 50/50. Bike has also never been in a shop. Some folks argue that spline lub is un-necessary others think differently. Maybe I've just been lucky, point is who knows??

 

Oh, have I ever mentioned that I just love the performance I get from my 1150 with LC-1? Hi Craig