BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

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Beemeridian wrote:Finished the final threadlock and torquing and went for a 90 mile ride, hitting 110 mph on many open stretches. Ran like new.

Woo hoo...!!! Good work.

Dave,
Did you replace those needle bearings at the FD end of the swingarm? There was a really good article by Paul Glaves in the October ON about replacing those rear needle bearings with a new design using an inner race with a brass bushing made by JL Enterprises. Paul's belief is that the front swing arm bearings are robust enough to use the OEM needle bearings but those rear bearings are always worn when he takes them apart on bikes. He recommends replacing with the race/bushing combo. They cost a LOT but supposedly are better and are a lifetime part.

I checked last night at the web site that sells the parts and they are on back order since that article came out. They sell for $120. I wrote them a note asking if that cost was for both bearing/bushing sets or for just one. ( I assume you need one set for each side of the swing arm) I'll pass on what I hear from them.

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You have removed the FD again? I am impressed by your perseverance and your attention to detail!
I did not want to mention this previously because I thought that you were done but if the alignment is off by 1/2 spline, you need to turn the yoke 180 degrees and try again.
Hope this helps!

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I've looked at the official BMW shop manual on disk several times for both the 1150R and 1150RT and can't find any mention of aligning the drive shaft yokes in the same plane. It sounds like this was mentioned in a Clymer manual only and I wonder how important it really is. I don't know where Carlos found the picture he posted on this thread.

The official manual says: "CAUTION: The universal joints for universal shaft and rear wheel drive must be installed in the same position." pg. 33.21 .
Clymer and I did not make it up. That's how all U-joints work.

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Beemeridian wrote: I guess by the "universal shaft", they are not referring to dealer pricing

The official manual says: "CAUTION: The universal joints for universal shaft and rear wheel drive must be installed in the same position." pg. 33.21 .Clymer and I did not make it up. That's how all U-joints work.

No offense intended, Carlos, but my page 33.21 of the R1150R BMW shop manual doesn't mention anything about the position of the drive shaft or U-joints. We must have different versions of the manual. The date in the front of the manual is "Printed in Germany 7/01". My RT manual has the same date. I believe you. Perhaps my copy is outdated and yours is newer.

U-Joints, when they rotate at an angle do not transmit the same even rotation as the shaft driving it. The output shaft side's rotation will be cyclical - - - it speeds up and slows down 2 times per rotation while the U-Joint center block flops and rotates smoothly. That's why FWD cars have (CV) constant velocity joints, so full lock cornering is vibration free.

With 2 or more U-joints, like any rear drive car/truck, they must be phased. There is conflicting info on which phasing method to use. Check out these websites:


This one deviates from the way my Nissan truck is configured:
Website:http://www.unisteer.com/help/index.php? ... ticleid=27









These match my truck:
http://www.4x4wire.com/toyota/tech/driveline/
http://www.custompistols.com/cars/artic ... joints.htm
Like this:




Also, on the advrider site there is a posting on phasing the U-Joints which they discovered that BMW did NOT do at the factory for every bike !!!
The post from Kevbo on page 2 explained it the best:

The yokes on the two ends of the driveshaft should be aligned such that if you put two rods through the holes where the U-joint bearing caps press in, the two rods would be paralell, like this:

=o]========[o=

or (viewed after 90 degrees of rotation)

=[o========o]=

NOT like these (90 degrees off):

=o]========o]=

=[o========[o=

Because there is an odd number (17) of splines on the slip joint, there is one and only one position where this will be true. There is a position approximatly 180 degrees off that will be _almost_ correct, but is actually ~10 degrees off.

If you can't figure out the ascii art, then crawl under almost any rear-wheel-drive cage, and see an example. Beware that many 4WD vehicles, and pickup trucks use a driveshaft with a splined joint (just like the paralever bikes) that may not have been assembled correctly.

The best way to determine the correct position is to assemble the shaft without the final drive, then mark the rear U-joint and the pralever housing with a sharpie to show the correct position, then snap the rear U-joint onto the pinion splines, and finish the job.

I'm going to be looking under several RWD vehicles in the coming days!!

Hey, thanks CycleRob for the post and the Advrider link. There were some good ideas about lining up the U-joints and marking them before putting the drive shaft in the swingarm.

This one would certainly be wrong if it were a driveshaft:

However, it's a steering column. Perhaps there are other geometric issues that we don't know about?

Awagnon: no offense taken! Besides, I keep getting things wrong (too much going on at work lately!): the caution on phasing is in the GS manual (shown below) and not in the R manual. Isn't that odd? If that's not an unintended omission, it must be that the larger angles that the GS driveshaft has are enough to make the alignment critical on the GS and not critical on the R.


Conclusion: the more I learn, the less I know.

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Beemeridian wrote: What is the likelihood that BMW could make such an omission in today's litigious society?

Like any large bureaucracy that collapses under its own weight of sheer process, procedure, and practice, I'd say the likelihood is high. No doubt there is a stream of Memoranda and email that discuss, cajole, emphasize and berate. Then someone just forgot to call the printer.

That BMW manual has a LOT of omissions. They don't hold your hand at all. I suspect it is for the experienced mechanic who already knows basic "stuff" and doesn't need every little detail explained, and somewhere there is some fine print with a disclaimer.

What is the likelihood that BMW could make such an omission in today's litigious society?

Cracking QD's spraying fuel, clutch plate spline failures, leaking FD's, several advrider members reporting random U-Joint alignments . . . . . the chances of leaving out the info and not aligning the U-Joints at the factory is apparently high. Maybe the assembly line workers thought, and testing proved, that the shaft axis angle between all 3 shafts was too small to matter. Maybe some disgruntled worker(s) were feeling vindictive and were able to get away with the hidden crime for years.

Tomorrow (or very soon) I pull both the gator boots back and check my U-Joints phasing. I'm guessing they'll be out of phase.

About the steering shaft not being a driveshaft . . . . it's kinda noticeable with it's small diameter shaft and large set screw on one end. Whether it's a driveshaft or steering shaft, if the U-Joints are not phased correctly it will likely be apparent to the operator. I was only concerned that a factory chose to phase the U-Joints against the rules. Maybe the article's author had to go with the steering shaft because it was the only one he could find that was out-of-phase.


.

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After looking at the U-Joint's rubber boots that mount to the swingarm, removing them to check the U-Joint phasing is NOT an easy job to do. The rear FD boot is easy. The front swingarm boot is barely visible and looks like the wheel, shock and maybe even the swingarm will have to be removed to gain access. Add this to my pilot shaft spline lube job list.

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