Drive Shaft - Questions

jrusell

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Greasing the driveshaft 1 time per year only takes an extra 10-15 minutes at most if you have the rear wheel off. My stance is why wouldn't you do it?
Anyone who has dealt with older BMW driveshafts wearing out will know the costs of not greasing splines.

Swingarm/ linkage bearings need to be done at some point as well.
 

steve68steve

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Seacoast, NH
My understanding of this torquing/ axle business is a GD&T thing:

There's a bolt hole pattern on the swingarm and a bolt pattern on the pumpkin (maybe I have that reversed). In order to assemble, the holes need to be at least as big as the bolt diameter, and with the exact same spacing as the bolts. Nothing in life is perfect, so there's some slop (tolerance) designed in: the holes are a little bit bigger than the bolts. This allows the parts to easily assemble and allows the spacing pattern of the bolts and the holes to be a little off-perfect and still go together.

But, this intentional slop means that the parts can be installed with different orientations to each other. IOW, bolt the pumpkin VERY loosely on the swing arm. Grab the pumpkin and twist it clockwise until it stops. Now twist it the other direction - it will rotate a tiny bit until it stops against the bolts - the amount it rotates is a function of the slop between the bolt and hole sizes and locations. This little bit of angular difference projected out to the other end of the axle is the issue.
You could also do this sliding up-down instead of rotating, and project an offset thru the axle; or sliding left-right effectively making the axle shorter or longer.

So getting the axle installed first means the wheel will force the pumpkin into the position that has the least stress. In theory, I'd guess this would be best accomplished with the rear wheel being made perfectly perpendicular to flat ground without any weight on it. In practice, this is difficult to achieve but my guess is that on the center stand is the best compromise between nothing or on the ground.

Keep in mind, this is really nit-picky stuff. I'm sure thousands of pumpkins have been removed and re-installed without any consideration of this and have been fine. The magnitude of errors and stress we're talking about is most probably negligible. I think it's one of those best-practice things that over-thinking pedants like me just feel better about doing.

I try to "worry less, ride more," but I have a harder time with "think less."
 

ballisticexchris

Chris Moritz
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Greasing the driveshaft 1 time per year only takes an extra 10-15 minutes at most if you have the rear wheel off. My stance is why wouldn't you do it?
Anyone who has dealt with older BMW driveshafts wearing out will know the costs of not greasing splines.

Swingarm/ linkage bearings need to be done at some point as well.
That's a great philosophy to live by.

Owners coming from low quality Euro bikes tend to falsely believe that a lot of maintenance is required for any bike. We all get to choose what level of PM we want to perform that makes us happy.
I'm guilty as charged for over-maintaining anything mechanical. I don't like breaking down. In all the years of riding I have only been left stranded once. Ironically it was on my XR600R. The engine locked up.

I do fully understand I'm in the minority when it comes to maintenance. I'm quick to admit that one of the biggest attractions to the Super Tenere is reliability.
 

ocgeek

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Aug 20, 2019
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Italy
One additional question as i've not seen this was touched

Is it difficult to slide back the Pumpkin and the attached axle back in the joint or it needs some fiddling e.g. by moving out the rubber grommet to access the joint with fingers and align joint to axle ?

Rear Arm.jpg

Thanks
 

Don T

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Mar 11, 2011
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Denmark
One additional question as i've not seen this was touched

Is it difficult to slide back the Pumpkin and the attached axle back in the joint or it needs some fiddling e.g. by moving out the rubber grommet to access the joint with fingers and align joint to axle ?

View attachment 61092

Thanks
I have done it a couple of times. The shaft slid back in the joint with a bit wriggling of the shaft. Not difficult at all.
 

Pmlsfo

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CONUS PNW
Hi folks I have a question , I was wondering how often the shaft needs to be greased? I could not find and maintinence mileage in the manual. Lubing the front of the shaft seems straght forward but am I correct in the assumption that there is disassembly necessary to lubricate the rear of the shaft?
 

EricV

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Hi folks I have a question , I was wondering how often the shaft needs to be greased? I could not find and maintinence mileage in the manual. Lubing the front of the shaft seems straght forward but am I correct in the assumption that there is disassembly necessary to lubricate the rear of the shaft?
The rear, pumpkin end, is lubricated by diff oil and grease. It does not have a maintenance interval. The front end is easier to access, but also is not really high maintenance. I did it twice in 100k miles.
 

Pmlsfo

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The rear, pumpkin end, is lubricated by diff oil and grease. It does not have a maintenance interval. The front end is easier to access, but also is not really high maintenance. I did it twice in 100k miles.
Thank you for the reply I appreciate it
 

ocgeek

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and on top of what Eric already pointed out the rear end (pumpkin side) of the shaft is a sealed compartment.
Fiddling with that (which requires removing a cir-clip, etc..) may lead to leaks after reassembly. That end is not recommended touching unless showing some leaking signs already or at high mileage... just reporting what i read myself in other posts
 

ballisticexchris

Chris Moritz
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Hi folks I have a question , I was wondering how often the shaft needs to be greased? I could not find and maintinence mileage in the manual. Lubing the front of the shaft seems straght forward but am I correct in the assumption that there is disassembly necessary to lubricate the rear of the shaft?
I would suggest cleaning/lubing the splines in shaft/wheel and changing diff fluid every rear tire change. IMO, the service manual is incorrect with their lubrication intervals for us off road guys. Slab riding you can get away with a lot longer intervals.
 

EricV

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Opinions vary. The cush drive splines should be cleaned/lubed every tire change. It's easy, you have the wheel off already. But this thread is talking about the drive shaft. There is no need to pull the drive shaft every tire change. That's hugely overkill for anyone. As far as the diff fluid goes, your descriptor is not a specific one. You go thru tires in 4k. Others go thru tires in 12k or more. If you change the diff fluid every oil change, (4-6k miles), you will discover that after about 5-6 changes it generally stops coming out dark and starts looking like what you poured in. At that point, changing it every other engine oil change, or less often, is more reasonable. Yamaha spec is every 16k miles or 24 months, (7-7 in the owner's manual)
 

ocgeek

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I have done it a couple of times. The shaft slid back in the joint with a bit wriggling of the shaft. Not difficult at all.
As i was after a "whole maintenance" (i got the bike used as 20K Km and it had 5 years, last oil change was 3 years back..) i did the joint greasing while after diff oil change
I lubed the shaft and greased the gear engine side (not visible in the pic as i did grease it after ...me genius...) The interior of the arm was pristine and no signs of rust anywhere...
Reinsertion of shaft was quite simple (it engages the gear engine end almost by itself / rotating a bit the pumpkin)
I did mounted the pumpkin a bit loose, rear wheel to spec and then i torqued the pumpkin nuts to spec... to make sure of the proper alignment. Seems everything is back together :p







 
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Checkswrecks

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Don't know i checked now and i see those
1. Easiest way is with the photo on a hosting website like SmugMug or similar.

2. Right click on the photo and COPY IMAGE LINK

3. Put the cursor in your post where you want the photo to go. Click on the photo icon above with the sun/moon over the hill.

4. Click on the BY URL (looks like hand cuffs), right click in the box, and paste in your photo link. '

5. Click INSERT and you should see the photo.
 

Checkswrecks

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And fwiw, I pull the drive shaft and lube the splines each tire change with moly grease. It just takes removing the 4 nuts and sliding it out. I change the diff lube at oil changes.
 

ocgeek

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1. Easiest way is with the photo on a hosting website like SmugMug or similar.

2. Right click on the photo and COPY IMAGE LINK

3. Put the cursor in your post where you want the photo to go. Click on the photo icon above with the sun/moon over the hill.

4. Click on the BY URL (looks like hand cuffs), right click in the box, and paste in your photo link. '

5. Click INSERT and you should see the photo.
I use Google Photos
and that's exactly what i did (and do everytime)
I can see the pictures in my post above; really don't know...

EDIT: I reloaded the PICs not sure it is showing up now for you too. Hope so
 
Last edited:

ocgeek

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Italy
And fwiw, I pull the drive shaft and lube the splines each tire change with moly grease. It just takes removing the 4 nuts and sliding it out. I change the diff lube at oil changes.
The manual actually calls for molybdenum grease on the wheel gear coupling
while lithium soap based grease on the splines (engine side coupling end)
 
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