Oil in exhaust

A rebuilt engine will chuck out some oil until all the bits have bedded back in. Beyond this you might have worn rings, worn bore or worn valve guides to check out. These engines do tend to eat valve guides. My Commando has two that are loose in the head and consequently leaking huge amounts of black gold.

Drop your right exhaust and have a look in the port. If there is an obvious dribble running down from the guide that could be the problem.

If the whole area is wet with oil then it could be rings, inlet guides or an over-active oil-pump relief valve.

I had this problem on my Dommi with pressure fed rocker spindles, oil came out of exhaust ports

They can push too far into head so the ears on the spindle plate don't hold them the right way round causing flooding of rockerbox

I think there was a thread about this somewhere but can't find it

Worth a check

Rocker spindles incorrectly fitted can be a cause of oily engines. Generally however, both cylinders tend to be affected to some extent.

Peter suggests that the problem is confined to one exhaust port.

I came across a similar problem but it turned out to be an inlet stem sealhad poppedoff. It then goes up and down with the valve and acts like a pump!

Also long ago on a domi 99 it turned out to be a loose exhaust valve guide in the head. but unlikely on a Mk3.

Paul