Water in Drive shaft

[jp9094]

While doing my annual service, I drained the final drive oil, which looked like it had just come out of the container it was so clean.

When I drained the drive shaft I could see it was the color of coffee with a lot of cream indicating water contamination. My question is where is the water getting in from? I rarely ride in the rain (maybe 3 times in the last 12 months). I did just pressure wash the bike a few weeks before the service however. I thought it might come from the tachometer cable which has an old rubber cover but thought that would contaminate the transmission oil, which was fine when I drained it.

Baffled!

[donbmw]

I would think the drive shaft boot has a hole or the clamps are loose. Can’t see any other way water can get in.

Don

[Barry]

The drive shaft is the only place I have found the gear oil to be contaminated with water. It only happened the once and slight contamination at that but I never discovered how it got in.

Your rear drive oil being clean is familiar, so much so I've given up on annual changes. I do low annual miles and the same oil is rated for life time use in a car differential so it should last more than 2000 miles in the bike doing what is actually a lessor duty as there are no hypoid gears.  But the potential for water contamination is still there so I do inspect it visually at every service. The gearbox and final drive are easy enough just remove the fill plug and take a small sample in a syringe. If it looks clean squirt it back in again and button up.  Can't do that for the drive shaft though so it has to be changed.

After rambling on I'll get to the point. Although I've never done it before I too power washed the bike before taking it to a classic show at the weekend.  I did try to be careful where I aimed it e.g. not at wheel bearings but your post is a timely reminder that I need to inspect the oil again.

[Bob_Roller]

Check the clamps that secure the rubber boots .

There is a small piece of metal that goes across the gear area of the clamp, it's channel shaped .

It's supposed to be tack welded to the clamp, if it's missing, you can get a wrinkle  in the boot and get water into the driveshaft area .

One of my second hand R65's had this, and the other had a standard radiator hose type clamp, they don't work in this application .

There is also a sheet metal tang that the clamp needs to go under, if it's over the tang, the boot is not secure .

[Barry]

I check all the oils and no sign of water.

[jp9094]

Took a look at the rubber boot and could not find any rips, tears or holes.  Confess the inspection was not 100 % as it is difficult to access the posterior portions of the boot.

Did find that the rubber boot clamps required at least 5 turns each to get them tightened up. Am hoping this was the cause of the problem and this was the fix. Any further advice appreciated!

Regards,

[Tony Smith]

Did find that the rubber boot clamps required at least 5 turns each to get them tightened up. Am hoping this was the cause of the problem and this was the fix. Any further advice appreciated!

The most likely source of the water is the hose you used to wash the suds off  at some point when you gave the bike a good clean.

By the way, and I think this pays well into your professional area, if you ever do need to replace that boot, the absolute best thing to use to work it into position prior to applying the clamps is a set of 4 or 5 artery forceps - straight, 45 degree and 30 degree. The artery clamps turn a miserable job into a 5 minute affair.

[Semper Gumby]

Wow it has been a long time.

In addition to the boot and clamps...

Check the rubber bell where the speedo cable goes into the transmission.  If this is cracked, replace.

Then get some large diameter shrink wrap tubing.
Put a small bead of your favorite RTV around the top of the bell and pull the shrink wrap down over the top of the bell and shrink the tube onto the bell and cable.

Also if your speedo cable has breaks cracks in the sheath or the outer coating has been scrapped off, water can get in and run down into the drive shaft.

Good luck.

+1 wut Tony said.  When ever i replace the boot (every 15k Miles btw) the air in the garage becomes thick and foul.