Spline Drive on K series

there was an article in the last issue of On (or whatever it is called) about repairing the spline shaft -

do these wear out like that often? or was this a freak occurance

I factor in the cost of a new chain when buying other bikes - should I factor in this job if I buy a k with 90K on it?

What flavor K are you thinking of?

If, for example, it was a K75, I might. You should always ask about the splines. And if you're going so far as having a mechanic look over the bike or you feel up to it, definitely make an assessment of those rear splines. FWIW, those on my old K, with 120k+ miles when I sold it, were looking very used, but still holding fine.

FWIW, Hansen's BMW in Medford, OR will do the job for under $500, and that includes a new drive shaft.

It's a consequence of the design. It's my understanding that, with proper maintenence, total mileage isn't an issue. Without periodic maintenence, splines will dry up & start to wear on each other. This for both rear drive <> driveshaft and clutch disk <> trans input shaft. Antiseize has to be refreshed. The question is how often. I think there are mileage & time maximums, but any more often than those depend on riding style, miles per year and climate/environment. Refreshing the rear drive spline is relatively easy, the clutchplate is another story. I'll yield to the several experts who view these forums for better details. I'd appreciate their wisdom, on both parts of the topic, for my education, too.

Working on a schedule of disassembly and relubing every 20K miles or so has kept the splines on my 1991 K100RS looking almost new. I use some really sticky high-moly content stuff from Honda. It seems to stick better over time than the BMW recommended lube. Your 90,000 mile bike might be just fine, it might be on the verge of total failure or more likely it is somewhere in between. The problem is you won't know until you take it apart and look. Figure on a day long project the first time, you are going to need a good torque wrench, some fairly large sockets and ratchetable allen wrenches to do the job properly. It gets quicker with practice and the tools you have to buy will pay for themselves the first time you do it. I'd rather not go into details but make sure you torque the brake caliper bolts correctly on assembly...

After 16 years and well over 100,000 miles of BMW riding I am convinced that a good part of the brand's reputation for longevity is due in good part to the fact that you have to strip them so far down on a regular basis to do things like lube the clutch splines.

Steve

brian thompson said:

there was an article in the last issue of On (or whatever it is called) about repairing the spline shaft -

do these wear out like that often? or was this a freak occurance

I factor in the cost of a new chain when buying other bikes - should I factor in this job if I buy a k with 90K on it?

Click to expand...

As Scott pointed out - these have to be factored into buying a used K bike.. and perhaps moreso on a K75.

Ok - the facts - from one of the spline-gang (from the IBMWR mailing list - where this was an ongoing project/research for several years..)

The splines to worry about (and there are other ones on the bike - but not worrysome ones):

1. Driveshaft/rear-drive spline. This is a sliding spline with a slight offset motion to it due to the use of a single universal joint in the driveshaft (paralever bikes don't have this concern - two U joints).

Wear on this is considered "normal" - but can be greatly delayed by regular maintanence and inspection of the splines. As someone else mentioned - Honda Moly60 is the lube that we've had good results with. BMW#10 is a disaster in this application. RedLine makes a synthetic moly lube that one person had very good results with.

The maintanence is simple - every other rear tire swap (or 10-15,000 miles - whichever comes first) you want to relube this spline. IF is has Honda Moly60 - it's really a simple job. You can do it (greatly simplified version) by putting a board under the rear tire to support the tire - loosening things like the brake caliper and wiring going to the rear drive - then unbolting it with the 4 big allen bolts that hold it to the swingarm. At that point - you can slide it rearwards far enough to see and lube the splines (a nice 1/2" wide artists brush works well).

If it has never been lubed, or unfortunately was lubed with BMW#10 - it's a bit more complicated since you should remove all traces of old lube, inspect the splines for wear (a fingernail is the best test - if you feel a step in the spline surface - it's worn) and then lubricate them with your lube of choice. The reason to clean them first - often different lubes don't mix well with each other.

If you do this on a regular schedule - chances are very good that your driveshaft splines will outlast your interest in the bike (ie - more than 100k miles, some WAY more..)

2. The other splines of interest are the clutch/transmission input shaft splines. More of a job. I can do them on a K75 without ABS in about 90-120 minutes now. Add 15 minutes for ABS. The K75 was particularly prone to failure of these splines - perhaps due to the way they were shipped to the US (long story that I'll skip) - the shipping distorted the transmission to engine alignment, causing a mis-alignment that wore these splines out - at very regular intervals (about 16-18k miles - like clockwork). An early indicator of a problem with these splines is difficulty in downshifting, especially 4-3 and 3-2 (which should be very smooth if things are OK..)

We can assume with 90k miles on the bike - this bike didn't suffer this fate and the transmission/engine alignment is OK.

In this case - I'd want to open it up and clean and lube the splines with Honda Moly60. If the splines are in decent shape - you can then forget about them for at least 20,000 miles (mine looked good enough I'm waiting for at least 30,000 miles before examining them again).

This job requires R&R of the reardrive, swingarm, transmission - and is a fairly major job. There are lots of details on doing it on the IBMWR website under the K-techpages.

That's the spline story.. if we had some webspace I could post some photos of good and bad splines to give you an idea - but the fingernail test is my acid test. Draw your nail UP out of the spline valley - it should go smoothly from bottom to the top of the spline. If you feel a step or catch - the splines are worn. I'd have to see really good detailed photos of the cleaned splines to give you some idea of how bad they are..

HTH,

Do you have photos on your site, Don? You can link the images here using the IMG tags.

Another place to consider getting a rebuild done is from Bruno's in Canada. They actually a bit more metal to the end, and heat treat it. I am anxiously awaiting the return of my splines from them to see if they are as good as everyone says they are. I believe the cost was about $250 or so. Not quite sure as it was a birthday/Christmas present thing from my parents. I think that my dad likes to help perpetuate the cycle of motorcycle addiction in our family.

I knew they were out there....

Two thumbs up to "deilenberger" for enough detail to satisfy the "AR" in me. The way they were shipped ?? wow. But now: does anyone have knowledge/history with Loctites' copper filled anti-seize model C5-A, label says it's good to 1800F (900C). I've always trusted Loctite, but it'd be an expensive assumption here.

KBasa said:

Do you have photos on your site, Don? You can link the images here using the IMG tags.

Click to expand...

Nope.. but I could prolly do that when I get a chance. Club newletter has priority tonight

Re: I knew they were out there....

CustomSarge said:

Two thumbs up to "deilenberger" for enough detail to satisfy the "AR" in me. The way they were shipped ?? wow. But now: does anyone have knowledge/history with Loctites' copper filled anti-seize model C5-A, label says it's good to 1800F (900C). I've always trusted Loctite, but it'd be an expensive assumption here.

Click to expand...

Antiseize in general isn't a lubricant. Temperature isn't the problem on either spline - it's impact load, sliding motion combined with an axial offset (well - on the clutch - the axial offset only occurs IF the engine/trans alignment isn't correct).

The plus with moly based lubes - moly actually plates itself to the metal when it is under load, creating a soft, slippery wearing surface. If the actual lubricant (which is grease) fails - the moly helps prevent damage - at least for a while.

We did try other lubricants - one which was made by Dow Corning had a very high moly content - but the base lubricant wasn't that great - and wear was visible. The Honda lube seems to do a good job - it's readily available (they use it on Gold-Wing driveshaft splines - which have the same sort of problem).

BMW recently came out with a new lubricant - I haven't tried it because I can't afford to sacrifice a driveshaft/rear-drive if it doesn't work well - but at least they have given up on BMW#10 lube.

The temperature reference was more for abrasive/galling tolerance than environmental. I'd always thought of anti-seize as the next higher viscosity relative of a gear lube, but apparently it's intent/formulation is quite different. I've got some homework to do....

CustomSarge said:

The temperature reference was more for abrasive/galling tolerance than environmental. I'd always thought of anti-seize as the next higher viscosity relative of a gear lube, but apparently it's intent/formulation is quite different. I've got some homework to do....

Click to expand...

Isn't the purpose of anti-sieze to prevent electron transfer that makes dissimilar metals get stuck together? I've always wondered how it worked, but never been sure.

Anti-seize VS persistive lube?

ARF! I'm info-challenged here. I know the dissimilar metals & large temperature cycle applications. I'd just projected it onto as the next gooier of molybdinum(?) disulfide type of chain lubes. Is there a physical chemist in the house?

KBasa said:

Isn't the purpose of anti-sieze to prevent electron transfer that makes dissimilar metals get stuck together? I've always wondered how it worked, but never been sure.

Click to expand...

Actually - not. It just forms a non-binding layer between two metal surfaces (which could be dissimular or the same metals). It works by having small particles in it that basically are free to move a bit. It will help keep moisture out of the metal to metal joint, which helps prevent corrosion.

As an aside - I got REAL familiar with galvanic action on dissimular metals when I owned sailboats. Stainless screws into an aluminum mast was almost a guarantee of corrosion and snapped off screws when you went to remove one - unless I smeared (tech-term) the stainless screw with silicone grease before installing it.

The grease excluded air and moisture, and formed a barrier preventing the electron transfer. Screws treated this way unscrewed easily and looked perfect even after years of salt-water exposure. There are some specific marine grade anti-seizes made - which in my experience cost a lot more and never worked as well as the old Dow-Corning Silicone vacuum grease I used.

If you ask for DC-4 that will get you the silicone that Don referred to. I used to use it all the time, and it works great for all kinds of stuff.

Holy Crow-

You guys are a bit more technical than some other groups I belong to!!

Thanks for all the info about splines and spline service
If push comes to shove I may have to request contact info on these spline refurbishing guys.

thanks again

brian thompson said:

Holy Crow-

You guys are a bit more technical than some other groups I belong to!!

Thanks for all the info about splines and spline service
If push comes to shove I may have to request contact info on these spline refurbishing guys.

thanks again

Click to expand...

There's a reason we keep Don around. Between the pieces of feces he's always flinging around his cage are some technical gems.

Does he make you call him The Don too?

Clutch / Transmission Splines K75

Background :
I just lubed the rear splines on my 1995 K75 with 13k miles on it. The rear spline was essentially dry but not worn, the front drive shaft spline still had lube visible. Lubing both was very easy ; used the Honda 60 lube everyone has praised.

As the rear spline was essential dry, I'm wondering if I ought to do the trans splines ... By rights I shouldn't need to, as it up/down shifts smoothly, giving no indication of problems, plus the BMW maint schedule says 40,000 miles for this lube ....

The trans spline lube is significantly more involved, so would like to delay it if I could, or see if there's an easier way.

Question :
Having never done the BMW trans spline lube, not sure how tight clearances are, so this is probably a real dumb idea ... But having worked on manual car transmissions before, and lubing throwout bearing forks etc, here's what I was thinking. Would it be possible to inspect / perform a clutch spline lube with everthing in situ, if a 3/4 inspection hole were drilled thru the bottom of the bell housing? The hole would be filled with a black rubber plug. I'm sure I'll just do it by the book , as I don't want to butcher the bike in anyway (it's in pristine condition, and I want to keep it that way ), but just had to ask , as if it did work , would enable me to easily stay on top of spline lubing this bike ... Thanks in advance for any feedback. I'll readily accept a "don't even think about it, it won't work " from the resident K bikes gurus. Thanks ... Todd Traver

Re: Clutch / Transmission Splines K75

tjtraver said:

Background :
I just lubed the rear splines on my 1995 K75 with 13k miles on it. The rear spline was essentially dry but not worn, the front drive shaft spline still had lube visible. Lubing both was very easy ; used the Honda 60 lube everyone has praised.

As the rear spline was essential dry, I'm wondering if I ought to do the trans splines ... By rights I shouldn't need to, as it up/down shifts smoothly, giving no indication of problems, plus the BMW maint schedule says 40,000 miles for this lube ....

The trans spline lube is significantly more involved, so would like to delay it if I could, or see if there's an easier way.

Question :
Having never done the BMW trans spline lube, not sure how tight clearances are, so this is probably a real dumb idea ... But having worked on manual car transmissions before, and lubing throwout bearing forks etc, here's what I was thinking. Would it be possible to inspect / perform a clutch spline lube with everthing in situ, if a 3/4 inspection hole were drilled thru the bottom of the bell housing? The hole would be filled with a black rubber plug. I'm sure I'll just do it by the book , as I don't want to butcher the bike in anyway (it's in pristine condition, and I want to keep it that way ), but just had to ask , as if it did work , would enable me to easily stay on top of spline lubing this bike ... Thanks in advance for any feedback. I'll readily accept a "don't even think about it, it won't work " from the resident K bikes gurus. Thanks ... Todd Traver

Click to expand...

Don't even think about it, it won't work

The design of the clutch is such that there is no clear path to the splines without removal of the transmission.

Some dealers use a shortcut of moving the tranmission back about 1" and then using a long brush to slobber (tech-term) lube on the part of the splines that are exposed.

I don't recommend this. If the lubes are incompatible (and BMW #10 and Honda-Moly60 are incompatible) - you're likely to make things a lot worse. There is also the worry about excess slobbered on lube getting on the clutch disk.

If you're comfortable R&R'ing a car transmission - the K bike one really isn't all that bad. You do need a means of supporting the bike withtout the centerstand/sidestand and rear wheel - but various techniques are described in detail on the IBMWR K-tech pages.

Plan on a full day the first time - once you get some experience at doing it (and know exactly which wrench fits what and what order things have to come off) - it can be done in about 90 minutes by two people doing it on a lift.

Despite the low miles on your bike - the bike is now about 10 years old - for peace of mind when riding to distant places this riding season, if it was me - I'd do the clutch spline lube.

And as always - clean up ALL the old lube from the splines and then use lube of choice (as you noted - we've had very good luck with Honda Moly-60.

Best,