Leak at drive shaft "boot"

[DieselDave]

Forgive me if this question is phrased poorly. I don't know exactly what the area in question is called and, in the absence of any regular riding buddies, you all get to be my support group.

 

I noticed a slowly spreading stain at the junction of my drive shaft and the rear wheel. Over the past 3 months it has gone from just a trace to the leak you see in the attached photo. (larger photo linked here http://us.f2.yahoofs.com/bc/400d96e2_101...f9JyqEBegbUlYVV )

 

 

Is this:

a) normal.

b) abnormal but not critical. Get it looked at during your next service

c) Dear God, Boy. Don't drive another mile until you get that fixed!

 

Your help is appreciated. Thanks.

[Tony_K]

Minor leak that has road grime and brake dust mixed in.

Get some Castrol super clean or like product spray it on then rinse it off.

It will then be clean and you can now trace your leak on your next few rides.

 

Keep the super clean solvent away from that sticker if you want to continue to read it.

[Mudman]

Looks like a rear drive pinon shaft seal leak, but no one can be sure until it is inspected. The leak could be originating from the gear box output shaft seal too. The drive shaft runs in a dry environment so this is begging for corrective action. If you get it early it may be a fairly simple fix. Let it go too long it could get very expensive. You may want to check the fluid levels in the gearbox and rear drive and then schedule a visit to a repair shop. I wouldn't go cross country or ignore too long.

 

Good Luck

[David McClain]

Hi Dave, looks just like the leak I had on my K12RS last year. I drove it at least 5k miles before taking it apart but kept an eye on the tranny and final drive fluids. My problem wound up being the pinion gear seal. I took the drive to my dealer while I completed pulling the trans/clutch so I could replace the rear main engine seal. I think they charged me around $150 to install new seals.

[Stan Walker]

b) abnormal but not critical. Get it looked at during your next service

 

I would do the following:

1) Clean up the outside, don't need to introduce dirt into the inside.

2) Loosen the clamp and clean up the oil you will find on the inside of the boot.

3) Clean the boot seating surface. Tighten the clamp.

 

If the amount of oil found in the inside of the boot was only a few tablespoons, I would ignore it for a long time. Maybe check it again a year from now. Many of the final drive pinion seals weep a little and never get any worse.

 

If the amount of oil found was a lot, say 3 or 4 ounces, then I would have the dealer look into it. Replacing the pinion seal isn't a hard task, but it does require some special tools.

 

Rarely does the transmission output shaft leak, but it has been known to happen. One way to determine which is leaking would be to run different colored oil in each.

 

Stan

[RockLives]

bet you are using synthetic....It happend twice to me, and stopped when seals were replaced and I went back to Dino oil in my final and tranny...

[Ken H.]

What Stan said.

 

Many a BMW weeps a bit there (who says only HDs leak?) and unless it is massive, you just clean it up periodically. You can have the seal replaced, but the problem may reappear.

[W8NONU]

I had the same leak and after checking, found that the seal at the rear of the tranny was leaking. Originally thought it was the rear drive, but ended up being the more costly tear the bike down version.

 

I would watch it closely and keep it clean to determine if the leak is increasing. Keep an eye on the fluids also. Once you see that it is getting worse it is time to tear it down. On the other hand if you are planning any long trips away from home and a dealer I would have it checked out right away. This could be a real disaster on a trip.