Sootydan, I agree that running warmer is better for wear and power but will have nothing to do with sticking valves. As the engine warms the clearance in the valves is reduced!!! If your valves are getting oil there not going to stick, unless there is moisture and a bit of rusting from lack of oil.
That is why I recommend a top oil when experiencing stick valves. Either MMO, or a good 2-stroke oil in the fuel for a bit mixed at around a 100:1. The oil in the fuel lubes constantly and the valve stems will get a coating when the engine is shut off or on
. Usually running a tank or two will clean off the rust and the valve can again be run "dry" with "splash" oiling handling the lubrication!
Dave Neptune
