HEET is to displace the water that is found in underground tanks, especially ones that dont get used a lot. I put it in sometimes and sometimes not. When I had my sled parked outside in Houghton for 5 months during the winter I never had a water in the gas problem. The problem with todays sleds is they measure gas going in so much better, but then again when's the last time you put HEET in a car? I wouldn't think you would need it. As an example I found a gallon gas can that was half full that I had left outside all winter, this was in Houghton. I put it in my truck because I thought I wasn't going to make it to the gas station, no problems.