Yes they are. If you put the bike in a warm basement the gas tank could vent fumes. Unfortunately an empty tank will cause rust. How about storing the full tank , with Sta-Bil, outside with the bike in the basement?rrover454 said:So, I'm moving to VA soon and a friend kindly offered to let me store my bike in their walk-in basement for the winter. One thing that concerns me is the fumes the gas may generate. Should I completely drain the tank before I tuck it away? I've stored stuff before in garages(full tank of gas with stabil), but that doesnt seem like the best option in this case. A basement is more closed in, and I dont want my generous hosts complaining of the smell/encountering possible problems. Is my concern well founded?