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Just finished shimming my valves and after starting and warming it up I noticed an oil leak that appears to be coming from somewhere around the rear of the valve cover gasket.

I wiped off the oil with a shop rag (as good as you can on a hot engine) and the leak looks like it "might" have stopped. It was late and I didn't have time last night, but will clean off all oil and check again when I get home this evening.

Anybody else ever had this happen?

Maybe it sealed itself up after the engine got warm?

Doubtful, leaks rarely fix themselves.
I bet you either you had oil already there from doing the work or the gasket is rolled, damaged or due replacement ?

Back2-2 wrote:Doubtful, leaks rarely fix themselves......

True.

The engine was definitely spotless after I finished and before I started the bike, so I'm afraid a new gasket will probably be needed. I guess I'll find out tonight.

Well, it's not leaking from the valve cover gasket. It appears to be puking out of this tube.


It has a little plastic clip that holds it in place over top of the breather tube coming out of the valve cover.


I did change the oil during all of this (pulled the carb and installed jet kit and shimmed the valves), but it's not overfilled.

Did I miss hooking this back up to something or is this really supposed to vent to the atmosphere in that location?

The carb has a vent tube that runs through the engine mount plates and is open to air. You are in good shape so long as you have the other end connected to the carb

riddler9 wrote:The carb has a vent tube that runs through the engine mount plates and is open to air......

That one is smaller. This one is a little bigger. Finally figured out that it's a tranny vent. I normally run Gear Saver tranny oil, which is red. They were out of that, so I put Maxima in it, which is clear. Not used to seeing clear lube in the tranny and that's why I thought it was engine oil....not tranny oil. I used the check plug when filling, but I did pour about an ounce over the cam and rocker area when I shimmed the valves.....but I can't believe an extra ounce would make it start puking out the vent. But I'm gonna remove the check plug to make sure.

Yeap, I had overfilled it . The tranny vent splits at a "T" right after exiting the case. The lower vent tube was clogged, so it was puking out the top. I've been riding bikes over 35 years and have never had a vent tube get clogged......wierd . But the leak is resolved, so now I can get back to tweaking the jetting.