Snowmobile Repair: using too much gas, yamaha v max, new spark

Question
i have a 94 yamaha v-max 600 2 cylinder single pipe. while out on the trail it used a tank of gas in forty miles of use. there was no gas leak found,but the exhaust had an oil leak which sprayed on the belt.could this have been the problem with the gas usage. i changed the gaskets on the exhaust and it does not leak anymore and i changed the belt and cleaned the oil from the clutch.is there anything else it may be?
i have found that mice have gotten in the engine compartment and i have taken care of that problem so far.but if you have suggestions on that matter i would greatly appreciate them.

Answer
Hello John,

  I have a pretty good idea of what happened, the sled probably sat all summer, before this ride. If that's correct, the inlet needles in the sled probably stuck open, and caused oil and gas to spray out of the muffler, kind of like flooding. My recomendation is new spark plugs, and, to be safe, cleaning the carbs throughly. Make sure the float height is set properly. That should have you ready to go. Let me know if you need any help at all. Good luck with the sled! --Arcticatman