My 1991 XR seems to be addicted to smoking. The bike has always smoked a little white smoke when it was started cold, but at the end of last year it got pretty bad. So this winter I pulled the head and had the valves replaced and the intake valves re-seated. I honed the cylinder and put in a new piston. I thought she had finnaly quit smoking! And she did for the first few months of this year, but now after a few long rides it is smoking again. In the exact same fashion. Start it cold and it will billow white smoke untill it warms up. After that its fine. What is causing this? Could it be my valve seals are gone already. Does anyone else have this problem? On a different, better note: My wife gave me permission to get a 650r next spring.