From blocking off the oil tank spigot and totally relying on the crankcase breather I clearly have excessive pressure in oil tank/engine as it was starting to leak around spigots etc and importantly pressure in the timing chest as the oil tank is trying to breath via the timing chest return hole and causing the timing chest to overfill (wet sumping?).
So 100% can see that if I block the crankcase hole and fit a oil tank breather like yours it should vastly improve. I have re fitted the oil tank breather pipe and run it to they rear mudguard and to be honest the bike runs a lot better with the oil tank pressure fully relived and the wet sumping has stopped. I do have more oil than I like coming out of the rear mudguard mounted breather pipe (oil tank level at bottom of dipstick) so may refit the catch can until next full engine strip and think about blocking the crankcase hole up.
So time to replace that oil ring and modify and refit the catch can!
Never a dull day!!!
But is running amazing well, torquey, responsive and actually quite smooth, defiantly a keeper!
stinkwheel wrote: ↑Tue Aug 24, 2021 4:34 pm
Allanfox wrote:Like the shithouse door blanking plate!
Also like the oil tank breather, how well does it work, does it keep the oil in?
Yes, because it's just a breather. The hole between the crankcase and oil tank has been blanked off and a normal duckbill fitted to the crankcases so they have their own breather. It occured to me that the oil tank was then pretty much sealed because it has a screw in cap and that's also the only way for the timing side to breathe (I may address this at some point). Thought it best not to risk a vacuum forming in the oil tank.