Sp 1000 Oil leak

[huklbery]

Hi folks I have been wrestling with a significant oil leak since I bought the bike recently.  It seems to be transmission related as the oil smells rank like transmission oil, as well as after changing the oil a check after a couple hours at freeway speed it appears to be about 1/4 of the .75 capacity low or roughly 8oz lower.   I had to change out the U Joint and added both a new boot front and rear o ring.  After pulling the swingarm, it does not look like there is anything going on past the trany drive spline the U joint remains clean of oil.

Frankly I'm baffled, the outside of the drive shaft swing-arm gets coated and the rear wheel flings it everywhere.  Bikes following get signification oil flung on them as well.  From the top of the shock on the right to the bottom it has a serious coat of oil.   At rest I do seem to have a drop now and again from the clutch bearing area. 

[Groover]

Other than the missing oil you measure, the rest to me sounds like a bad final drive seal. (The big one you see when you take the wheel off). Mine failed recently, and oil was all over the drive shaft tube on the swingarm like you describe, all over the rear wheel, inside the fender, etc.

You can post stuff like this (questions) in the general section. Maybe a moderator can move it.

[huklbery]

Other than the missing oil you measure, the rest to me sounds like a bad final drive seal. (The big one you see when you take the wheel off). Mine failed recently, and oil was all over the drive shaft tube on the swingarm like you describe, all over the rear wheel, inside the fender, etc.

You can post stuff like this (questions) in the general section. Maybe a moderator can move it.

I tilted the swing arm assembly forward and a fair amount of oil leaked out.  It has a vented cap with a plastic tube routed forward then around to just past the shock upper mount.  What does the sealing?  From the parts blow out diagram I only see a couple gaskets referenced. 

[Groover]

Sounds like someone modified the cap to be vented, probably to help stop (or hope to) a previous leak issue due to pressure buildup in the final drive. If I'm understanding this correctly, you are tipping the swingarm up and you see oil leak from the u-joint area?

If that is the case, nothing really seals the oil from the final drive from going up the shaft. Maybe a little from the sealed carrier bearing (which are typically of the sealed type) but I wouldn't really consider that a seal-seal.

If Molybdenum Disulfide was used in the final drive, the oil will be almost black and will be easy to tell the difference between the transmission oil. If that wasn't used, it's hard to tell the difference.

Take a look at this thread and see if it helps some.

http://wildguzzi.com/forum/index.php?topic=86432.new;topicseen#new

[Antietam Classic Cycle]

I tilted the swing arm assembly forward and a fair amount of oil leaked out.  It has a vented cap with a plastic tube routed forward then around to just past the shock upper mount.  What does the sealing?  From the parts blow out diagram I only see a couple gaskets referenced.

Oil would leak out when the swingarm/rear drive is tilted downward/forward - there are no seals on the pinion/input shaft. Also, there is no "vented cap with plastic tube" from the factory, so someone has added that.

Seals are numbers 25 and 45 in the diagram below.

[huklbery]

Thanks everyone for the help, its been illuminating to be sure.

The drive plug being vented and a lengthy tube, that is a common user add on with Ural's.  I think I need return to stock conditions as I suspect its venting everything in the drive. 

I'm going to see what I have in the Transmission as far as volume.  Honestly I expected a coat of oil on the new U Joint but there was no evidence of that.  The seal I'm looking at on the Transmission, is it removable in place?  I bought a 27mm socket that seems to fit, but is there a sacrificial metal retainer in front of the nut on the rear spline shaft? 



The other thing that occurs to me, if I leave the boot unhooked and leave it exposed *if* oil is escaping the back transmission seal it should no longer travel to the end but instead exit at the gap.


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[Groover]

I have successfully replaced that same seal on mine externally like that, so I would say yes you can.

And good logic on the boot-off test. Actually, makes a lot of sense to me.

[huklbery]

I have successfully replaced that same seal on mine externally like that, so I would say yes you can.

And good logic on the boot-off test. Actually, makes a lot of sense to me.

Do I simply remove that nut and the seal becomes accessible?  My eyes are so bad these days, its seems like there is something in front of the nut itself.                                                             

[Groover]

No, do not remove the nut. I think that has to be torqued down at a certain specification. The sealing face of the seal is larger than the nut. I removed mine with a hook tool, screwdriver, and lots of patience (without damaging anything). Then tapped the new one in actually using the old seal as surface initially, then I used a flat tool to tap it in going round and round without damaging and/or distorting it until it reached where it needed to be. Takes some patience.

Get some of these (or similar), no joke. Everything will make more sense (I used one similar to these I use when I work on my bike)

https://www.amazon.com/HEADBAND-MAGNIFIER-JEWELRY-GLASSES-BINOCULAR/dp/B014PVVCTM/ref=sr_1_3?ie=UTF8&qid=1496689918&sr=8-3&keywords=magnifier+headset

Good luck.

[thomas]

Hi
Did you ever find this leak?

[huklbery]

Hi
Did you ever find this leak?

I suspect it was the previous owners "vent" on the final drive for the most part.  I'ts back together now though I developed some electrical gremlins.  I need to get it to the CHP office to have the VIN verified as it had a simple typo on the registration.  If this is how healthcare is going to be run its not going to be pretty. 

At some point I hope to do more riding and less wrenching but its giving me a good foundation on its  construction/maintenance