Burnt Valve?

[Haerera]

With the motor out of the frame

The busa has developed a bit of a smoking habbit lately. Intermittent. I'd start the bike in the morning to be greated by plenty of smoke. The next day it would start smoke free. It always stops smoking after a bit of riding.
Currently 60k on the clock (2003 model).

I thought it might be valve stem seals. Pulled the engine out on the weekend, removed cams and spark plugs. Screwed a pipe into spark plug hole of cylinder 1 and clipped it to the air compressor. Pressurised it with the compressor to find air rushing out from the exhaust port from around the second exhaust valve. Tried the remaining cylinders and they were all fine. My guess is a burnt exhaust valve?

I'm trying to remove the head but can only fit 1/4 inch sockets onto the head bolts. These don't have the strength to loosen them. Has anyone taken the head off their busa? If so how did you undo the head bolts??