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2004 R1150RT oil leak from rubber boot

L

leibjo

Guest
I have a 2004 R1150RT with a small oil leak from the rear boot of the drive shaft. I'm wondering what would be causing the leak and how much work it be for me to fix it? I'm ok with a wrench and enjoy working on my bikes but this bike is new to me and I shy about tearing it apart with out having some idea of what I'm getting into.

I'm totally blown away with how much I've learned about the R1150Rt from the Forum. Any help would be appreciated.IMG_0775.jpg
 
I think what you have there is a leaking pinion seal in the final drive. This is a very common problem. If you search for pinion seal or final drive seal in this forum there is a dearth of info on the issue and how to repair it.

A good friend of mine has repaired a lot of them and has never had one come back leaking again. His method is to not just replace the seal but also to use sealant on the large castle nut that is in front of it. He found that final drive gear oil is often leaking past the threads on the castle nut also.

Mine leaks right now too. I drain a tablespoon or two out of it every several thousand KMs, check the level and top up if necessary between changes. If there is no metal in your drained oil you should not get overly excited about a small leak and just fix it when convenient.

Like not in the middle of riding season for example. :D
 
start off by monitoring the situation- clean it up, drain fluid from boot, ride a thou of 2, see what you've got. a small amount of fluid makes a big mess, but des not mean a repair is critically necessary.
 
leak

A LOT of oilheads do that. And by a LOT I mean A LOT. My RS has leaked for the past 100,000 miles. My RT has leaked for the past 40,000 miles. As noted, a little oil goes a long way to making a big mess. The fd oil level has never been low on either bike. BTW - fd oil STINKS. This is normal, so when you change the fd oil, don't panic if your garage smells like some dinosaur died in there.
What most of us do the first time is:
Remove the clamps from both ends of the boot
Pull the boot back from the swingarm so you can 'look' up the tunnel towards the transmission. You only need to see the first inch or so.
If the tunnel is dry, you have a fd pinion seal leak. They (almost) all do that. This is NOT a problem that needs to be fixed. If you fix it, it will probably leak again, so save your time, money and aggravation and ignore it. Use a paper towel to wipe out the inside of the boot as much as possible. Put the clamps back on the boot. Wire ties strung together work well to hold the boot in place (three strung together on the big end). Wipe the outside of the fd and swingarm off. Go ride. It will probably get oily over the next 5-6k miles. Both my bikes leak off and on. Sometimes I wipe them off every 5000 miles. Sometimes it is longer. If it leaks enough to show up on the outside over the next 1000 miles, wipe it off and ride. If it repeats after that, maybe you will want to fix it, but you were probably sloppy about wiping out the boot...
If the tunnel is oily, you have a transmission output shaft seal leak that needs to be fixed. Rather rare. That is a different discussion.
 
some notes on above: you can get large wire/zip ties that require only a single piece. they will be just a little bit wider than the OEM items, but they are a fraction of the price. (ACE carries those kinds of things). leaking rear trans seals are either not that uncommon, or i have an uncommon bike- mine started leaking around 80K miles. wanted it to be the FD, so i sent it our for a reseal job. but it didn't fix the leak, so i did the rear seal. fwiw- i saw no tracing coming down the driveshaft tunnel before the repair.
 
Wow! I'm contentiously blown away by the contributions members make to help one another! Thank You!

I'll clean the boot, have a look up the tunnel and watch my oil level.

Cheers,
 
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