Mayonaise in the drive train.

Shunt

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Bugger!

Ive had a few dribbles on the back wheel for a few days, So stripped to looksie today.

I did have a days playing in the mud and quite deep water a while back, So I'm hoping its from that.

But why is it collecting at the bottom of the swingarm. Ive looked up the swingarm to the gearbox and can't see a trial of mayonnaise.

Gearbox oil is very clean



Ignore the black, Its an old bucket.

Fd oil is very emulsified.



Im wondering if water has got into the Fd, Mixed with the oil. Then as there is too much in the Fd its been pushed out of the seal?

Anyone else experienced this?

Im going to flush the Fd out later today and refill it to get it clean again. Any chance that this will be the end of it or is there more doom an gloom to follow me?

Edit- Bikes a 2005, No drain plug or breather on the Fd
 
The water collects in the lower boot, as the fd cools it draws the water into the unit,emulsifying the oil,
Have a good feel for play in the pinion bearings,if there is excessive play the unit will need a rebuild
Mike
 
Cheers Mike, That makes sense to me. I'll give it a good pulling around and let you know how it is :thumby:
 
I'm sure I've mentioned elsewhere on these boards, the issue I had with the final drive boots while on a trip in the US and Canada. Took the bike into the BMW dealer in Portland, OR, for its scheduled inspection (20k? Can't remember.) They took down the drive and reported back to me that it was full of mud, oil and water and I "must have been doing some serious off-roading for it to have got into that state!" (I hadn't, of course.) Anyway, the long and the short of it was, they told me, the drive was on its way out and I'd be unlikely to finish my trip without a replacement ...

Lying toads. Drive started leaking 'oil' onto the back wheel 1000 miles up the road in Williams Lake, BC. I called the dealer who said, "I told you so. Better call ahead and order a new drive from the nearest dealer. It'll take time to come in and it's going to cost $$$$." :eek: Luckily the nearest dealer (Kalowna, BC) didn't buy Portland's story and told me they weren't ordering anything until they'd seen the bike. Turned out the water and muck was purely due to perished boots. What appeared to be oil was an emulsified mixture of oil and water coming from a leaking seal. We had to hang around in Kalowna for a few days over the Canada Day weekend (not at all unpleasant :D), till the parts came in, but it was a cheap fix and the drive caused no further bother. Mide of this parish has the bike now.
 
nice to hear mrsroynie, I had been doing some mild off-road stuff. Including quite a few deep puddles (cylinder head height) hence my post hoping it's not too expensive.

I can't feel any play in the Fd anywhere. Pinion or wheel. I'm just filling it with some cheap gear oil before I run it round the block an change it again for some proper castrol stuff.
 
It could be the gearbox oil seal dribbling and mixing with water trapped in the swing arm case. It could also be water mixed with the FD oil having pushed out through the seal. Check all bearings and seals and the speed sensor O-ring.

Also check -


  • Driveshaft UJs. Any tight spots = the UJ rollers are failing and wont last much longer. On mine, the rear UJ was tight outside is usual (small) angle of movement.

  • Suspension trunnion. Mine was goosed. You need a heat gun to strip it down so its not a quick job and service grease gets ignored.
Mikeyboy does a good rebuild via parcel post of your choice.
 
Well. I got it all cleaned an back together yesterday afternoon. Haven't ridden it. Maybe today, definitely tomorrow.

I got my good torch up the swing arm and can't see any moistness around the gear box seal. Also popped the gearbox boot off. All looks good up there at the moment.
With the Fd. I can't feel any play at all on it same with the Uj's. It's like yours bendy toy. Tight on the edge of its movement but lovely and smooth in normal range.

What is the suspension trunnion??

At the moment it's looking like I'm getting away lightly. I'm hoping I have anyway.
 
My rear UJ was stuffed. Free in the small range if normally sees bug tight outside that. A sign of oval rollers in the UJ.
The Trunnion is the FD pivot bearing. It's another load of expensive needle rollers being misused. They don't like small oscillations.

You might be able to replace the FD input shaft oil deal with the self tapping screws method.

Change the FD oil and replace the speed sensor O- ring.
 
To identify whether an output shaft seal or FD input seal has failed, loosen both clamps off the boot and carefully clean out any old oil residue with paper towels and solvent (I used panel wipe). Then dust talc up inside the swing arm and around the FD input shaft, refit the boot, go for a ride and have a look inside the boot when you get home. You'll easily see where any oil is coming from.

Mine was the gearbox output shaft seal.
 
Many thanks all. I've used it to work an back today. About 30 miles.
Hasn't leaked anything yet.
But I'm feeling dog rough an can't be arsed to go out there tonight an poke about.
May do after diner an a Jd an coke may feel up to it ;)

Thank you for clearing up the trunnion Buisness that feels ok. No movement or notchyness.
 
The trunnion needs heat to 100deg C to shift the threadlock. Use a high solids moly grease. Hopefully enough lube will remain under the brg rollers.

Mike is DA MAAN if it needs a rebuild. :)
 


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