Change after shimming

Thank you all for the input. I removed the head tonight and Wow, more carbon than is in my wife's jewelry box...LOL i wish...Anyways, a tremendous amount of carbon. I have not removed any of the valves yet, my spring compressor don't fit this head, so i ordered one that does. I did make a small effort to remove the valves the old fashioned way, but the double spring just made me a bit uncomfortable. I do believe that I have a bad guide seal, causing the smoking, however, with this much carbon i also think I have a small seating problem.. I was going take some photos, but got so involved, i guess my age does play some factors. Because it was not smoking before I reshimmed it I thought for sure I was simply pushing a corroded spot on the valve shank through the seal....More than like the extreme change in position simply fractured a dry rot seal....I will follow up with my results when I am complete...Again. thanks

All the seals are dry and cracking. I suggest Viton seals. You'll find the exhaust valves were seating on carbon. Be sure to get all the carbon out of the cylinders or scratching will occur. You may be able to clean the valves and seats, then lap them. I'd look into springs too.
Steve

Again, i would like to thank everyone for the help, after performing a head overhaul, the bike is running great. i am going to have to change out my cam chain tension er as it is slopping around a bit, other than that new guide seals and carbon removal took care of the problems. Safe ridding Tim

Great to hear.
Some guys would ride it until it stopped running and sell it.
Good job.
Steve