Sounds like you just need to pull the carbs apart and clean out the jets. When machines sit that long, the fuel can start to leave varnish deposits that can clog the main jets. Clean the carb, dump the fuel and put fresh in. You can also check your fuel pump by just taking off the fuel line and turning on the key to see if it's pumping. But I'm guessing you just have dirty carbs.
Jarrod Sheets
FD Racing
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