My bike is very cold natured. I have to give it a little shot of starting fluid and full choke to get it to fire up and run. Even then it takes about 20 seconds to run on its own. Once it starts it now runs great. It pulls strong all the way to 27 mph. It idles fine. The plug is a nice shade of brown just as it should be. However, if you turn the bike off for 2-3 minutes after it is warmed up it will not restart. Does anyone else have this problem or a solution.