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View Full Version : "R" Driveshaft Specs??



RSPENNACHIO
04-22-2009, 08:32 PM
Does anyone know who manufactures the 2007 to present "R" bike driveshaft? Or does anyone have technical specs on it?

U joint size
length
plunge
runout
balance
DOM / HSLA steel?
Spline profle for each socket yoke

RSPENNACHIO
05-06-2009, 02:09 PM
Helloooo...... echo........... echo.......

(Crickets chirping)......... cricket...... cricket.... cricket...

So many humble opinions:bluduh.......................

I thought I had a homerun when I picked up the latest ON, but no. I am just sure someone out there can help me.

PGlaves
05-06-2009, 02:48 PM
Of course not. BMW provides specs in service manuals for assemblies they consider to be rebuildable. They do not provide specs for assemblies that they do not consider rebuildable/repairable. Ergo: no specs that I have been able to find.

Of course they exist. They are in their design documents and their bidding documents for suppliers. They would be considered "proprietary" and thus not available to the general public as far as I can tell.

1aretea
05-06-2009, 10:17 PM
Rider Rob, what are you trying to do, reinvent the drive shaft ?

31310
05-07-2009, 04:57 PM
Paul, I read your excellent article in the latest MOA re driveshafts. Just changed the final drive oil on my '07RT and did not think of offsetting the U-joint as you recommend for several series. Before I rush out to pull it apart again, is my RT part of what your wrote about? Btw, to my surprise the splines were quite dry and very little moly in evidence; the dealer did change the oil at 600 miles two years ago.

1aretea
05-09-2009, 10:48 AM
With all this talk about drive shaft maintenance and lubercating the drive shaft splines every 40-50 thousands miles. Makes me wonder, how much does the drive shaft splines slide on each other when the suspension goes thru it's full range of travel ?

PGlaves
05-09-2009, 01:43 PM
Paul, I read your excellent article in the latest MOA re driveshafts. Just changed the final drive oil on my '07RT and did not think of offsetting the U-joint as you recommend for several series. Before I rush out to pull it apart again, is my RT part of what your wrote about? Btw, to my surprise the splines were quite dry and very little moly in evidence; the dealer did change the oil at 600 miles two years ago.

Yes - what I wrote in that column about phasing the universal joints applies to all paralever bikes with two universal joints - including your 07RT.

PGlaves
05-09-2009, 01:45 PM
With all this talk about drive shaft maintenance and lubercating the drive shaft splines every 40-50 thousands miles. Makes me wonder, how much does the drive shaft splines slide on each other when the suspension goes thru it's full range of travel ?

It probably doesn't have a lot to do with how far they slide and more to do with how much torque is applied when they do slide. Or in slightly different terms, how much force is pressing the sides of the splines together when they need to slide.

And I do want to add: I don't think paralever driveshaft splines need to be lubricated every 40K to 50K miles. Everything I've said or published about 40K to 50K spine lubes applies to clutch hub splines.

It probably ought to be in an article and not here, but there are two reasons that splines on monolever bikes wear and splines on paralever bikes seldom do: a) the contact area of the splines in the middle of a paralever driveshaft is about twice as big as the contact area on the monolever driveshaft rear splines; and, IF PROPERLY PHASED, the acceleration/deceleration force at the iniversal joints is canceled with the paralever system - but - with a single U joint in the monolever shaft, they cannot be canceled. See my column in the May ON.

1aretea
05-09-2009, 11:54 PM
Paul, thanks, now I can stop thinking about the drive shaft and more about riding. Had a clutch job 5000 miles, so my clutch splines are "good to go"

marchyman
05-10-2009, 03:30 AM
Yes - what I wrote in that column about phasing the universal joints applies to all paralever bikes with two universal joints - including your 07RT.

:confused:

I haven't had mine apart, but isn't the drive shaft on the hexheads one piece? It seems that way from the drawing for my '05 GS, at least. It looks like the U-joints are part of the driveshaft assembly and the assembly is manufactured in phase. There is nothing that a mechanic can do with respect to adjusting the phasing.

17663

Or am I missing something (quite likely :D)

PGlaves
05-10-2009, 03:53 AM
:confused:

I haven't had mine apart, but isn't the drive shaft on the hexheads one piece? It seems that way from the drawing for my '05 GS, at least. It looks like the U-joints are part of the driveshaft assembly and the assembly is manufactured in phase. There is nothing that a mechanic can do with respect to adjusting the phasing.

17663

Or am I missing something (quite likely :D)

No - it is two pieces but sold only as one part - both pieces together. The rear piece withdraws from the front piece when the final drive is removed. And should be reassembled "in phase" when the final drive is reinstalled.

31310
05-12-2009, 04:40 PM
Have the final drive apart now on my '07RT to drain & refill as per the new specs. The splined input shaft into the final drive is not connected via u-joints. Paul, are you referring to a disassembly/reassembly of the drive shaft yokes/u-joints? That makes sense to me how it needs to be reassembled as you refer to you in your article. Otherwise, it appears you simply lube the splines and put it back together.

PGlaves
05-12-2009, 06:07 PM
Have the final drive apart now on my '07RT to drain & refill as per the new specs. The splined input shaft into the final drive is not connected via u-joints. Paul, are you referring to a disassembly/reassembly of the drive shaft yokes/u-joints? That makes sense to me how it needs to be reassembled as you refer to you in your article. Otherwise, it appears you simply lube the splines and put it back together.

Huh?

The pinion (input) shaft on the final drive is splined - male splines. The very back end of the back U joint has the mating female splines. That joint is held by a spring clip in a groove, so it doesn't slide right off but can be levered off.

The front yoke on the rear universal joint has a male splined section that slides into the female splines on the front half of the driveshaft.

The front driveshaft piece has female splines at its front that slides over the male splines on the transmission output shaft. This joint is also retained with an internal spring clip so needs to be levered off the transmission putput shaft to remove it.

The male splines in the back half of the shaft and the female splines in the front half of the shaft - where the two parts fit together - need to be lubricated if apart. And the two pieces need to be assembled toether so that the two U joints have the proper orientation. That is phasing the U joints.

31310
05-12-2009, 06:49 PM
Sorry to be so dense, was hoping to post before you read this. Once I pulled it apart again, it became very obvious what you were referring to Paul. I made it more complicated than it needed to be.:blush

marchyman
05-12-2009, 08:06 PM
The front yoke on the rear universal joint has a male splined section that slides into the female splines on the front half of the driveshaft.


I did some digging. The Hexhead -- at least the R1200GS -- has a one piece drive shaft. The following is from a BMW press release at the time of the R1200GS release (emphasis added)



The pivot point of the axle drive unit resting in the swinging arm has been moved down to provide a more favourable geometric arrangement which also incorporates greater stiffness. The bearing point, in turn, has been reinforced to match the higher load and forces from the more powerful engine.

With its improved kinematics, the driveshaft no longer changes in length as a result of geometric conditions. This also helps to save weight, since the length adjustment unit formerly fitted is no longer required. The shaft itself now comes as one single piece and - like before - runs without oil in the shaft sleeve.


// marc

kthutchinson
05-13-2009, 10:26 AM
The pinion (input) shaft on the final drive is splined - male splines. The very back end of the back U joint has the mating female splines. That joint is held by a spring clip in a groove, so it doesn't slide right off but can be levered off.

Paul,

After watching a couple of hexhead final drive oil changes at a Tech Daze last year, it seems that the the male splines on the final drive pinion shaft simply slide out of the female splines at the back of the rear U joint, without needing to be levered off, and that there is no spring clip. Could these sliding splines be what changes the driveshaft length on the latest hexheads?

Karl
2007 R1200ST

RSPENNACHIO
05-13-2009, 01:32 PM
Paul,

After watching a couple of hexhead final drive oil changes at a Tech Daze last year, it seems that the the male splines on the final drive pinion shaft simply slide out of the female splines at the back of the rear U joint, without needing to be levered off, and that there is no spring clip. Could these sliding splines be what changes the driveshaft length on the latest hexheads?

Karl
2007 R1200ST


Something is weird here...

The splined female end (on both sides) of the shaft are there to allow for axial plunge (travel) as the suspension moves up and down. The cerclips "should" be on the male shaft ends and there to hold the shaft in a neutral location. If you saw final drive pinion just slide out of the socket yoke (female end) then the circlips are used like stops to keep the shaft centered If this shaft is two peices then the front and rear halves would be joined by a center slip mechinism. Having a slip at the trans, center and pinion seems a bit much.

PGlaves
05-13-2009, 06:18 PM
Live and learn. Now I'm going to have to go out and find one to take apart and figure out what they really did. If in fact there is no need for sliding motion - it is an improvement.

Just when I think I know something for sure I find out I got it all wrong.

Sorry! mea culpa!

kthutchinson
05-13-2009, 09:58 PM
For a look at the final drive pinion separated from the rear of the driveshaft on a hexhead, see this Link (http://www.jimvonbaden.com/R1200_Final_Drive.html) on Jim von Baden's site. Scroll down about half way.

kthutchinson
05-13-2009, 11:12 PM
:confused:

I haven't had mine apart, but isn't the drive shaft on the hexheads one piece? It seems that way from the drawing for my '05 GS, at least. It looks like the U-joints are part of the driveshaft assembly and the assembly is manufactured in phase. There is nothing that a mechanic can do with respect to adjusting the phasing.

17663

Or am I missing something (quite likely :D)

I thumbed through the Parts Fiche on the Max BMW web site. The drawing referenced above is used for several models, both K and R. For the hexheads, only part 1, the driveshaft, is listed. Part 2, the circlip, is not. However, for some K bikes, both parts are listed. I guess not all Paralevers are created equal.