Thanks to you both. Yeah the bike starts first kick, idles well and runs well. I think if it wasn't for the fact that I'm an engineer I probably wouldn't pick up that something was wrong.

The erratic temp originally I believe was the fuel damaging the head gaskets as once they were changed the temp characteristics were better and increased slowly again.

Originally the fuel leaked through and as I kick started the bike it hydraulically locked, I tried again as didn't suspect this and forced all the fuel out through the exhausts so maybe the fuel didn't reach the crankcase? or maybe little did and didn't reach up to the seals? (I'm hoping). I'm not sure how long it could have been like this for it was 2 years ago and I remember starting the bike frequently but also had a baby and was studying.

The possibly seized power valve could answer the question of the smoke from the right exhaust when opening up but doesn't explain the high temp at idle.

I will carry on and update you when I'm done and let you know. if the power valve doesn't work then I will go for leak down test.

Thanks

Ian