I always run premium gas in my Snowmobiles. No ethanol. I have heard this before that if you empty your gas tanks down to about a gallon and then put in about a gallon of race fuel that the carb stay a lot cleaner over the summer.I start my sleds during the summer but with the season near the end for a couple of my sleds has anyone have good or bad story's about this.I would run on race fuel for only five minutes I would think that would be long enough to have the fuel in all the lines and carbs.I have always cleaned my carbs myself every year on all five sleds.Only thing I've seen bad because of gas is my water traps have been replaced on every sled.Carb boots only on one.Any good advice on this.Thanks