Oil on the rear rim.

[audiomick]

I noticed it today: a patch of oil on the inside of the rear rim, consistent with it having dripped off the final drive whilst parked.

It is a bit hard to tell with that lovely wrinkle paint, but it seems like a fair bit of the outside of the final drive housing is oily, and the breather valve thingy looks like it is oily enough to perhaps have been the source.

I dare say I'll need to clean it up and do the talcum powder thing to get a better idea where the oil came from.

Would anyone care to speculate in advance about where it is likely to be coming from?

A good guess might save me looking up some blind alleys.

[p6x]

 

[audiomick]

Thanks for that link. I had forgotten that topic was there.

 

I neglected to mention in the first post, that the rear wheel was out not so long ago, and the final drive got new oil when it went back in. The bike hasn't been ridden much since, so it is fair to assume that the new fill of oil is still "settling down".

It may be that the bike always did blow off a bit from a fresh fill. This is the first time I've filled it, and I have to admit to not having checked the level in the rear drive at any time since I bought the bike up until I refilled it.

[p6x]

1 hour ago, audiomick said:

Thanks for that link. I had forgotten that topic was there.

 

I neglected to mention in the first post, that the rear wheel was out not so long ago, and the final drive got new oil when it went back in. The bike hasn't been ridden much since, so it is fair to assume that the new fill of oil is still "settling down".

It may be that the bike always did blow off a bit from a fresh fill. This is the first time I've filled it, and I have to admit to not having checked the level in the rear drive at any time since I bought the bike up until I refilled it.

There you have it...

The simplest reason always makes sense.

I did my gear box and final drive on my V11, and used a syringe to measure the exact cc. Obviously, Guzzi did not specify what standard conditions is the measurement valid for. I did not observe any seepage or leakage. Same thing with the Quota. I was often checking the breather when stopping. It remained dry.

[audiomick]

8 minutes ago, p6x said:

a syringe to measure the exact cc.

I'm quite sure that I was very close to the right volume. I added one of these for the molycote, and as the last drops of that went in, it started to run out of the level control opening at the back.

https://www.louis.de/artikel/motorbike-mos2-shooter-20-ml/10080192?filter_article_number=10080192

However, I don't exclude that possibility that it might still spit a bit, even if it is theoretically all correct.

That's why I'm looking for opinions here.

[GuzziMoto]

Clearly it could be coming from either the seal or the breather. Generally if it is coming from the seal there will be more, seals tend to fail and leak a lot, while if it is only a little it is usually the breather. Especially if it doesn't get worse fairly quickly.

I would clean the drops off and watch it for a little while. If it is the seal you will know it fairly shortly. If you don't see more than a few more drops it was likely spitting out the breather.

If you are really worried about it dust the rear drive housing with talcum powder or similar. That should show you the trail the oil took, and where it started.

[audiomick]

7 minutes ago, GuzziMoto said:

If it is the seal you will know it fairly shortly. If you don't see more than a few more drops it was likely spitting out the breather.

Ah, that makes sense. Thanks for that.

7 minutes ago, GuzziMoto said:

If you are really worried about it dust the rear drive housing with talcum powder or similar.

Yes. I'm not so much worried as annoyed, but the talcum trick is likely to be the next step.

[docc]

If you can park the bike upright and open the level plug to drain overnight, any overfill will self correct.

Otherwise, seal failure will manifest by dripping off the bottom of the bell flange if it is the large, inboard seal.

Or at the right swingarm junction if it is the deep, inboard seal.

[audiomick]

Thanks for the pictures @docc.

As I already wrote, mine seems to be oily all over the final drive case, so I reckon the breather might be the candidate. We'll see when I find time to have a closer look.