Easy Rider and Chopperguy

Fall is here and the temperatures are dropping. When you run 50W and it is below 50F, the old chop likes a little warm up period. How long should you let an old chopper warm up? Used to be that my warm up period was about the same amount of time it took to smoke a roll-your-own. Now I wait until the dew has completely cooked off the headlight. Of course you could just wait until you hear the engine running smoothly, but that's no fun.