bought a used 3050 (I think that's the model) and cant get it running. It was stored inside, about two years I think. I put a new plug in it and fresh gas, and hooked a 10 amp battery charger to it. It cranks over great, but just wont fire. It has spark, not sure if it's getting any gas, or if the carb is plugged up or what. Sprayed some carb cleaner at the air filter but got nothing. Sprayed a little directly into the cylinder, reinstalled the plug and got a single cough out of it. So, I know the battery is junk, but it seems like it oughta start on the charger. I have been reading posts on here for two days, I saw somewhere where a car charger is not advised for these little batteries. I've always used it on fullsized atvs without a problem, do you think I fried something?

I thought at first I might have a bad stator or cdi or killswitch, but from what I've read those would all prevent me from having spark. I think it's a fuel delivery problem. How can I check this? I don't know much about carbs. Also, this machine is like new, very little use at all, so I'm leaning away from it being parts failure or valve/timing adjustment. From what I know it ran great for a few hours worth of riding, then got put away and forgotten. If I pull the air cleaner and run carb cleaner though it while cranking will that clean up any gumming issues? That worked on a 98 500 I just got.

 

let's get the easy stuff out of the way, if you got spark, compression, good timing and fuel, it'll start. sounds like you got it all BUT fuel seeing how it coughed on a lighter hydrocarbon. SO, let's get you to pull the carb and clean it. all ports, both jets. here's a video on how to clean an atv carb. now the carb is generic and may not match your carb, BUT the concept is the same.
look through youtube as there are many how to vidoes like this one.

 

now, on your battery charger. no more than 2 amps/hr or you'll do damage. it is most advisable to disconnect the battery from your terminal wiring/leads. as far as cranking it, remember it is a 12 volt system so you can jump it from your car/pickup battery with jumper cables if needed. please do not run a quad without a battery as it is vital for the completion of the electrical circuit.