Spline Lubrication Clarification

[r80andr100rt]

What concerns me is that the abrasive dust around the shaft now becomes a grinding paste when mixed with the lubricant.

The shaft on my R100RT spun smooth at 9K. It was practically new. BMW did replace it under warranty.

 

[AnnapolisAirhead]

What concerns me is that the abrasive dust around the shaft now becomes a grinding paste when mixed with the lubricant.

The shaft on my R100RT spun smooth at 9K. It was practically new. BMW did replace it under warranty.

Yikes. Thankfully yours was covered under warranty--I am well beyond that point.

From what I understand there are two ways to do it, the short way is to back the transmission out about 3/4" and use a long stiff brush to lube it. But this way doesn't provide as much opportunity to clean like the longer way of removing the transmission completely.

 

[BUDDINGGEEZER]

Sounds like the so called "BMW Certified" mechanic that installed wheel bearings in my brand new (recalled) Snowflake wheel 2 years ago. Didn't bother to grease those bearings as they came with oil on them from the factory. Like that was meant to last. He didn't even know about preloading them. Same guy thought that balancing carbs was a real PITA and would take at least "a couple of hours" to get just right. Naturally at $90 per hour, plus any shop materials. Pray tell, what the heck shop materials are required to balance 2 carbs. Does he charge for each of the shop towels he uses to wipe behind his ears?

I no longer bother with the so called "mechanics" at the dealers. They may know a bit about the compujunk on the newest bikes, but have no clue about the basics of being a real mechanic.

I know of a BMW certified tec that fits this description perfectly.

I also know of a Japanese brands shop that in fact does charge for shop towels used as shop materials .

Ralph sims

 

[shire2000]

Rocketman, You stated "Based on one experience with one mechanic you condemn them all? Wow, talk about painting with a broad brush..."

If you lived where I do, you would probably feel the exact same way. I live in Qualicum Beach on Vancouver Island. There is only 1 BMW dealer on this island, in Victoria 170KM south of me. That dealer tries very hard to service all the newer bikes and will try to service an older bike if given the time. Unfortunately, they do not have any mechanics/techinicans that know much about Airheads or anything older than about 1995. They have admited this to me directly. They are more than happy to order parts, but tend to charge way to much for them. And the coffee they serve is not all that bad.

The next closest BMW Dealer is in Vancouver, which requires a ferry trip at a cost of $100 round trip and a minimum of a whole day just to get to the dealership and back. They refuse to work on anything older than 1990. And will not work on any Airheads whatsoever. But, the coffee they serve is quite good and they include some nice little pastries as well.

All we have left is small independent shops. Again the closest independent shop is in Vancouver and they are Airhead specialists. The owner is an older Factory Trained BMW Technician who went independent when the Vancouver Dealer started to refuse to work on the older bikes. He saw a good market and went for it. I have had good service at a reasonable cost from this independent. He has stated that when he was training at the factory, back in 1970 and again in 1982, that BMW recomended that splines be lubed at every major service. Major service to him is every 2 years or 30,000 miles. That might be a little overkill, but at least they get lubed. They don't serve coffee, they service bikes. They send people down the street to a coffee shop.

If you really take a hard look at the newer bikes or cars, there really isn't all that much for a real mechanic to do. It seems to me that in most cases, the "tech" will plug a computer into the vehicle and the computer does the diagnostics and tells the "tech" what part to replace. That is all fine and dandy, to a point. But what do they do if that part was not the problem? They plug the computer back in and find another part to replace. Eventually, they replace the part that was actually broken and charge you for all those other parts as well.

Ooops, Sorry about the rant. I get a little carried away sometimes.

 

[dennisdarrow]

Yikes. Thankfully yours was covered under warranty--I am well beyond that point.

From what I understand there are two ways to do it, the short way is to back the transmission out about 3/4" and use a long stiff brush to lube it. But this way doesn't provide as much opportunity to clean like the longer way of removing the transmission completely.

If one removes:
rear tire
swing arm pivot pins
battery and mounts
air filter and housings
throw out/clutch arm mechanism
rear sub-frame bolts

One can easily pull the transmission back so that the input shaft is totally exposed and ready to clean/lube. Doing less than exposing the whole shaft perhaps, leaves to much crud around the mechanism. Total time, maybe 3 hours.

Doing this maybe every 30K is great to do; but I feel more important when one first acquires one of these machines because one never can be sure what the PO did. After one does this, cleaning and lubing all those parts you pulled, you can feel pretty good about that end of the drive line.

Ride...........Dennis

 

[rocketman]

Rocketman, You stated "Based on one experience with one mechanic you condemn them all? Wow, talk about painting with a broad brush..."

If you lived where I do, you would probably feel the exact same way. I live in Qualicum Beach on Vancouver Island. There is only 1 BMW dealer on this island, in Victoria 170KM south of me. That dealer tries very hard to service all the newer bikes and will try to service an older bike if given the time. Unfortunately, they do not have any mechanics/techinicans that know much about Airheads or anything older than about 1995. They have admited this to me directly. They are more than happy to order parts, but tend to charge way to much for them. And the coffee they serve is not all that bad.

The next closest BMW Dealer is in Vancouver, which requires a ferry trip at a cost of $100 round trip and a minimum of a whole day just to get to the dealership and back. They refuse to work on anything older than 1990. And will not work on any Airheads whatsoever. But, the coffee they serve is quite good and they include some nice little pastries as well.

All we have left is small independent shops. Again the closest independent shop is in Vancouver and they are Airhead specialists. The owner is an older Factory Trained BMW Technician who went independent when the Vancouver Dealer started to refuse to work on the older bikes. He saw a good market and went for it. I have had good service at a reasonable cost from this independent. He has stated that when he was training at the factory, back in 1970 and again in 1982, that BMW recomended that splines be lubed at every major service. Major service to him is every 2 years or 30,000 miles. That might be a little overkill, but at least they get lubed. They don't serve coffee, they service bikes. They send people down the street to a coffee shop.

If you really take a hard look at the newer bikes or cars, there really isn't all that much for a real mechanic to do. It seems to me that in most cases, the "tech" will plug a computer into the vehicle and the computer does the diagnostics and tells the "tech" what part to replace. That is all fine and dandy, to a point. But what do they do if that part was not the problem? They plug the computer back in and find another part to replace. Eventually, they replace the part that was actually broken and charge you for all those other parts as well.

Ooops, Sorry about the rant. I get a little carried away sometimes.

I sorry if I don't see your point in how my comment is "painting with a broad brush" I was simply saying I think is not reasonable to condemn all mechanics based on one individual regardless of how many may be available.
Perhaps if you stated your case as you just did above it would have taken on an entirely different context. I find it much more informative than your previous statement and can much better appreciate your circumstances.

RM

 

[lkchris]

You'll find very few mechanics at dealerships these days that have been formally trained in Airhead tech.

Perhaps this mechanic feels justified in extrapolating Oilhead and K-bike knowledge to the Airheads, but that's incorrect in this case.

In addition, one needs to understand the gigantic chasm between "mechanic" and "engineer." If you're not an engineer or have never worked closely with them, it's almost incomprehensible.

Check what Oak says on this issue, and try to mostly ignore what mechanics say.

 

[rocketman]

You'll find very few mechanics at dealerships these days that have been formally trained in Airhead tech.

Perhaps this mechanic feels justified in extrapolating Oilhead and K-bike knowledge to the Airheads, but that's incorrect in this case.

In addition, one needs to understand the gigantic chasm between "mechanic" and "engineer." If you're not an engineer or have never worked closely with them, it's almost incomprehensible.

Check what Oak says on this issue, and try to mostly ignore what mechanics say.

fortunately for me most machinics in my area that I deal with are ones that have been at it since the days of the airhead and some few learned by doing more than by schooling, just as I have learned what go me where I am today.

RM

and yes I know the differance having worked with both during my years as a draftsman and CADD operator becuase I worked directly with both on countless projects and even did a little design work myself.

 

[MrGrocer]

Egads! Airheads are old machines and deserve this one little piece of babying. Every two years, I would remove the cutch and do this (I was told not to use the shortcut by a treasured airhead wizrd friend.)

Its worth it, just to become familiar with your buddy.

 

[PHMARVIN]

Hi,
I'm sure the pictured grease is a fine grease for certain applications, just like the BMW #10 red grease. It was fine for lubricating the control lever pivot points, but NOT for spline lubes. For spline lube grease, hie thee down to thy Honda dealer and buy a tube of Honda 60 Moly Paste. The tube is not cheap, but is probably less than half of the cost of the (tiny) tube of BMW "spline lube" and will probably last your lifetime.

 

[globalrider]

The shaft on my R100RT spun smooth at 9K.

I doubt it spun smooth due to it not be relubed...not in 9K (from new). It was probably due to a material defect or poor QA as far as the clutch disc to input shaft fit.

 

[keelerb]

I did this just a little while ago. With even fewer steps:

"If one removes:
rear tire NOPE
swing arm pivot pins YUP
battery and mounts NOPE
air filter and housings YUP
throw out/clutch arm mechanism YUP
rear sub-frame bolts" NOPE

Can't remember if I removed the bottom shock bolts - but I don't think so.

My first time; probably took 1-1/2 to 2 hours, total. Used instructions from Snowbum's site. Not difficult at all.

Used Krytox, we'll see how good it holds up. I plan on doing every 12-15K, or two years, whichever comes first. Better safe than sorry....(yes, I am a bit anal....!)

 

[jforgo]

Actually, this can be done without even removing throwout - but I don't see why you wouldn't service that as well.

You do not need to touch shocks to do this at all.

As to Honda Molypaste - I have used this. It goes on very well, is extremely slick, and gives a fabulous clutch feel. However, it seems more "slicky" than "sticky". Quite early on, the transmission-to-engine gap begins extruding this stuff. It seems to fly off quickly. Another local airhead I discussed this with had the same experience - big mess in clutch cavity. This does not seem to happen with the BMW stuff, which feels much more "sticky". I would suggest the Honda stuff needs rejuvenation more frequently.

Lastly, what is "krytox"?

 

[keelerb]

Krytox is some relatively new, teflon (I think) based lube for high pressure applications. Writeups I've seen describe it as essentially a wonderdrug.

E.g., http://motorcycleinfo.calsci.com/Shaft.html.

I've also used it on the rear wheel splines, but have found it drips (?) out on the back wheel so I'm not sure about that application.

Anybody else used this stuff on clutch and/or rear-wheel splines?

 

[nrpetersen]

My thoughts:

The need for clutch spline re-lubrication depends on the amount of accumulated manufacturing error there is in your transmission-to-engine interface. Some bikes have everything aligned nearly perfectly, in which case there is little or no spline wear. Some are manufactured with a lot of error in that alignment, and these are the horrible failure examples we have been forced to read about.

How do you know what you have? Keep track of the clutch disc-to-transmission backlash as seen thru the starter hole. Look for wear debris in the clutch cavity. As long as this backlash doesn't increase, and the area is clean, there is no spline wear and you have probably been blessed with a bike that was made properly, and there is no need to tear it down for arbitrary relubing.

On the other hand, if the clutch disk to transmission backlash increases substantially, there will be debris around inside the bell housing, and you have a lemon and should be either relubing it or peddling the bike.

My 2000 R1100 at about 20K miles had about 1/8 inch lash at the OD of the clutch disc when it was new and the interior of the bell housing was pristine, so I don't worry about it.

Anybody have any better backlash numbers? or other thoughts?

 

[108625]

Makes complete sense to me... Otherwise, I can't see why a tried and proven system (just about every car and truck ever built with a manual transmission or transaxle uses the same set up) needs this level of lubrication in a BMW and not every other application.
I have worked on a lot of hot rods and four wheel drives, each having both higher torgue, traction, and weight (and higher driveline stresses) than a lightweight, skinny tired, sixty-odd horsepower motorcycle, and never seen or heard of input shaft splines or clutch splines stripping out. In the case of misalignment, I've only seen pilot bushings/bearings fail. The resultant failure allows excessive play in the input shaft that usually ruins the front seal of the transmission, slinging fluid on the clutch and causing slippage before something catastrophic happens. It usually becomes quite audible too. You can say I'm comparing apples to oranges, but if you remove the vehicle surrounding the transmission bell, you'll see the mechanism inside is the same. I guess we all should pull apart our cars and trucks every 15 or 30 thousand miles and lube our input shaft splines.
I can imagine a bikes that sat for a long time, were improperly lubricated on assembly, or have been exposed to excessive water (fording rivers in a G/S?)
suffering from corrosion damage if not re-lubed. So yes, I would do it to an unknown used bike. But a daily driver that's operating normally? I doubt it.

Again, that's my zwei pfennig
Bob

 

[nrpetersen]

Two (usually) reasons cars etc don't have clutch spline problems:

1) The transmission input shaft sticks out comparatively far from the transmission such that it can flex, reducing the necessary spline fretting action.

2) Many vehicles have a pilot bearing which forces the input shaft axis to coincide with the engine flywheel axis reducing the necessary spline fretting.

Crosswise mounted engines in FWD vehicles sometimes don't have either feature. How they get by, I can't understand, unless it is superior quality control.

Think of a spline as an inside/outside gearset with the same number of teeth in both halves. If the rotating centers don't coincide precisely, the "gear teeth" become heavily loaded once per revolution, especially since they don't share the tangential load necessary to transmit the torque.

 

[108625]

Now we're getting into some good stuff...

Yes, all moving parts are subject to some "flex" meaning deflection or other distortion, however, that's what tolerances are for. Between play at the input shaft bearing and throwout bearing, and freedom of movement designed into the throwout arm/fork, any neccessity for "flex" should be accounted for before a rotating input shaft deflects enough to increase wear on the clutch splines.

Newer vehicles often stabilize the throwout bearing by mounting it on a tube surrounding the input shaft, the throwout arm can move it back and forth without affecting it's alignment perpendicular to the input shaft. Or they use a circular hydraulic clutch slave cylinder mounted rigidly and incorporating the throwout bearing. Such setups ensure smooth, evenly distributed pressure.

The clutch itself is aligned off the crankshaft centerline when you install it, but the first time you use it with the engine running will shift to the input shaft centerline of rotation like a spinning top. If the crankshaft centerline and input shaft centerline are too far off but parallel, excess vibration would result. If they are too far off but intersecting, one might not notice it as easily. This is where I agree with you, it's the only condition that would explain abnormal wear and spline failures to me.
Otherwise, there's no reason they should fail prematurely, or require lubrication so frequently unless BMW made them out of low quality material.

Bob
Gearhead (and hardhead)

 

[nrpetersen]

The clutch itself is aligned off the crankshaft centerline when you install it, but the first time you use it with the engine running will shift to the input shaft centerline of rotation like a spinning top. If the crankshaft centerline and input shaft centerline are too far off but parallel, excess vibration would result. If they are too far off but intersecting, one might not notice it as easily.
Bob
Gearhead (and hardhead)

No it does not become simply a vibration problem. Rather, if the crankshaft & transmission input shafts centerlines don't match, the transmission input shaft has to continually drag the clutch disc in an orbit on the flywheel face with the drag force being applied thru the spline. It will orbit once per engine revolution, which puts a helluva lot of sideload cycles on the spline system. Hence all the wear.

 

[bmw14651]

Spline Grease

Do you happen to have the BMW part number for the grease? I pulled the tranny from my '84 R65 that had sat unused for years. Spline and shaft were both rusty. As someone else pointed out, the exercise provided a great opportunity to easily service/lube a number of nearby components including t/o bearing assembly and swingarm pivots.

I picked up this R75/5 about 4 weeks ago now. I do not know the history on the splines, so I am going to just do it and check it out.

I picked up some grease for use on lubricating the throttle parts for my bike. The same mechanic that said to not worry about the splines told me to use this grease for the throttle. He said he had not used it yet and it was new from BMW. Funny part is it says on the bottle it's use is for lubricating the splines. Attached is a picture.

<img src="http://www.tkdan.com/tmp/lube.jpg" />