Unexpected spline lube problem

[leaton10]

 I posted a couple months ago about getting a hold of a pristine 95 K75, less than 6K miles.
Well, she'd been sitting up for over 10 years, but under good shelter, so was not much problem getting
her going.  Since then, new tires, new battery, progressive springs, and a new rear master cylinder.
Anyway - figured she was way overdue on a spline lube, both clutch and drive shaft.
  So I found some info about some shortcuts on IBMWR I think it might have been.
No problem doing the clutch, although it was not fun - got her done in around 5 or 6 hours.
It looked clean and no wear or rust.
  However, the trick mentioned in the article on the shaft lube, had a cool idea. It suggested not
Dismantling the swing arm, but attaching a hose clamp to the end of the drive shaft where it
comes out to attach to the rear drive. Then using a couple screwdrivers apply force to pull the driveshaft out
of the transmission end. This worked great, but I could not get the drive shaft completely out. It seems that
the driveshaft on the tranny end has some sloppy welds on it that make it too fat to be pulled out through the
end of the swing arm, since the end of the swingarm is flanged on the inside.
  So to make a long story short, I put it back and just lubed the final drive end.
I suspect the other end does not wear much anyway since it does not slide, but is locked in place by
the clip on that end.
  It still bothers me though to not finish the job, but last time I took a swingarm off a Beemer (R1100) I lost a couple of
the tiny needle bearings and it cost a fortune for the replacement.

Is this an oddball drive shaft. Should you be able to pull it out from the back?

Larry

[Scott_]

Not having owned a mono-lever bike I can't say with 100% certainty, but, I would probably say that no, the drive shaft should not be able to come out thru the swing arm. Most likely due to the U-joint at the transmission end of the shaft.

Yes, there should be a circlip that holds that end of the shaft in place, so lubrication is not as critical at that end as it is at the final drive end.

[F14CRAZY]

I lubed my driveshaft splines a few hours ago actually.

I do not remove the swingarm from the transmission either. The U joint on the transmission end is a snug fit when it comes out of the end of the swingarm but it comes out without much effort (or tools). I'm able to get the driveshaft completely out to clean and lube it. I use visegrips across the outside end of the driveshaft sticking out the swingarm then pop it off the trans output splines with a big screwdriver against the visegrips and the end of the swingarm...I use a rag in between to keep from marring up the mating surface. As Scott mentions there's a circlip that pops to let the driveshaft loose of the trans output and this prying takes care of that. It sounds like your technique worked though.

Based on how there's virtually no wear on the splines on that end of the driveshaft, I haven't worried much about cleaning and lubing the transmission output splines before popping the driveshaft in the swingarm. I goop a bit more Honda Moly 60 and don't worry about it.

Not sure why your driveshaft won't come out of the swingarm though

[motodude]

I have two K75s.  A '90 and a '95.  The drive shaft comes in and out of the swing arm on the '90 with room to spare.  The '95, not so much.

It is a bit of a struggle on the '95 but it does come out.  Replacing requires a good smack with a mallet.

There is no need to remove the swing arm.

Tom

[rbm]

Is this an oddball drive shaft. Should you be able to pull it out from the back?

Larry,  It does seem odd that you can't pull the driveshaft out through the swingarm.  Did you observe welds on the U-joint?  If so, it might be that the shaft was repaired.  If such was the case, it would have been installed on the transmission output shaft while the swingarm was off the bike.  Then the swingarm would have been installed over the driveshaft.

It should not be a problem to remove a standard drive shaft out through the swingarm without needing to disassemble the swingarm.  It is not a tight fit either, meaning removing and installing should be easy and problem free.  It's not the end of the world that the transmission output shaft splines did not get greased.  the driveshaft is captured on those splines with a circlip and movement is minimal, so wear is minimal.  The important ones are the clutch splines (for ease of shifting) and the final drive splines (for minimal wear).

[leaton10]

Thanks all
  Yes - there are some welds, so you must be right RBM. I'll just live with the problem until such time that I have to remove the swingarm.
Then I'll file the welds down so it comes out.

  There must me thousands like me that would like to know what the jerks at BWM were thinking when they designed this.
This is the same design that virtually every car uses. What would happen if BMW came out with a car that required you pull the
differential and transmission to lube once a year?  They would likely not sell another car till they fixed it.

  I've thought about ways this could be fixed. On the clutch end it seems that you could put a rubber or silicone sort of stretchy hose over both ends
of the clutch splines where it would slide up the output shaft. It would be flexible and stretchy enough to allow the clutch the small amount of
float and movement it needs to slide on the shaft. It would keep the grease in and the dust out. What do y'all think?

  On the driveshaft end where it meets the final drive, then those that have suggested plugging the end of the driveshaft seem to have the right idea
in my opinion.

[F14CRAZY]

Don't worry, I think the same thing all the time. I don't mind lubing the final drive much but the clutch splines are dumb. I still don't get why they need to be lubed and wear out as even really, really cheap crappy cars (Lada's, Yugo's, old Hyundai's, etc) never get worn out clutch splines and don't get greased.

[leaton10]

One of the main reasons I've been a fan of BMW motorcycles is because of the drive train.
I think it was a great idea to get rid of the maintenance headache of a chain.
I also think it was a great idea to come up with the single sided swingarm. Anyone that has changed a rear tire on a bike with
a chain knows what I'm talking about.
  However, seems we just traded one type of maintenance headache for another.

[F14CRAZY]

One of the main reasons I've been a fan of BMW motorcycles is because of the drive train.
I think it was a great idea to get rid of the maintenance headache of a chain.
I also think it was a great idea to come up with the single sided swingarm. Anyone that has changed a rear tire on a bike with
a chain knows what I'm talking about.
  However, seems we just traded one type of maintenance headache for another.

pretty much

[Laitch]

Those who want ease should avoid motorcycles altogether and lease a Corolla or live near a mass transit stop. :falldown:

[leaton10]

Yes - that would do it. However, as an engineer, I find it frustrating when things are not done correctly.
Take, for instance, a Jeep CJ I once had.
It took 10 minutes to put the top up, so I'd just put up with a little rain sometimes.
And the dash was put together with those bend over tabs like cheap toys used to have,
and the instrument lights were soldered in...

[Tuco]

After losing a chain years ago due to a broken master link, I'm good with shaft driven bikes and their idiosyncrasies