Just a thought. Exactly where the leak is showing there is an alloy plug in the timing cover sealing a drilling for the oil gallery to the crank feed. There is a (very) small possibility that it is leaking from the plug.

Quote from: briancairns on 09 July, 2025, 03:45:20

Quote from: Steve.S on 09 July, 2025, 03:35:19I've just had another thought. Is the screw hole adjacent to the leak in communication with the timing chest? If so, you may want to fit that screw with a sealant such as Hylotite Red, with, maybe a fibre washer.

I used Granville Clear Gasket Sealant around the area which leaks, so will do a test run later. If leaks again I will look at fitting a fibre washer etc to screw adjacent to leak. Don't think I will do cylinder compression leakage test. Also I think I will blow compressed air up the oil tank breather tube to ensure there is no blockage there.
cheers
Brian

ok, I blew compressed air up the oil tank breather, heard a pop, air flowing freely. Took bike out for 10 mile test run, slight oil weep from timing case and the odd spit of oil from timing case breather. I think that's the best I'm going to get.
thanks all for the marvellous advice.
Brian

Sorry for a potential hijack but why do we want to put anything on the gaskets?
Isn't it their job to seal the imperfections?
I'm seeing variations of (some kind of sealer) on one side and either nothing or grease on the other.

Just trying to get a handle on this and the best way to try to make my bike as dry as possible.

Thanks
Marc

Forks
Just filled the LH leg after doing the RH last week.
Pleasing news is that the RH drain plug was still dry where previously, with the incorrect washer, it had been very leaky.

Even so I found my biggest best fitting flat blade and gave them both a good tweak!
🤞🏽

I consider Wellseal old hat, there are plenty of other products on the market, why use gaskets if you can seal a face with something different, I believe Locktite can seal almost anything as long as you don't need a gap for things like gear boxes where the distance between is crucial.

TTJ

It must have gone somewhere - either leaked or burnt. Or the return side of the oiling system has failed somehow and all the oil's in the crankcase.

I think it was hylomar - the blue stuff - that was said to be developed by RR. I still prefer wellseal.

Don't know about "developed" but didn't R-R promote Hylomar?
Wellseal one side and grease the other is my preferred method.

Thanks for the steer Rupert. I took the cover back off and checked the oil seal.  I had ordered two seals: camshaft points and the clutch cover one.  The camshaft points one is correct. But the other seal is an imperial one marked 1.187 - 0.750 - 0.250.

This translates to 31.75, 19.05, 6.35
My research shows that 30.3, 20.6, 6.3 is the normal sizing for 40-0243. I think that explains why it was tricky to fit into the plate, and too tight on the sleeve gear.

The old seal (retrieved from the bin) was marked 70-3833 which is the same as 40-0243. The larger id is obvious.

Quote from: Steve.S on 09 July, 2025, 03:35:19I've just had another thought. Is the screw hole adjacent to the leak in communication with the timing chest? If so, you may want to fit that screw with a sealant such as Hylotite Red, with, maybe a fibre washer.

I used Granville Clear Gasket Sealant around the area which leaks, so will do a test run later. If leaks again I will look at fitting a fibre washer etc to screw adjacent to leak. Don't think I will do cylinder compression leakage test. Also I think I will blow compressed air up the oil tank breather tube to ensure there is no blockage there.
cheers
Brian