"It's been running"
Do you mean it's been running the last few weeks Or do you mean last Fall?
Bike carburetors hate this "new" gas the carbs get crapped up very easily if you don't drain the bowls through the winter OR run the bike.

If it hasn't run since last fall and wont start at all since you put oil in the cylinders, you can pull the plugs, then let it crank for about 15 seconds and see how it does then. I usually winterize with 2 cycle oil.
My Bike doesn't get winterized I ride 'til it snows , then I run it every 3 weeks until most of the salt is off the roads.

Suzuki 650, great first bike. Easy to work on and small enough to get your feet wet. Enjoy it.

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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html