My Sportsman 500 is a 2003 year model and while I was installing a new battery and did not notice the + and +and _ posts were opposite as original until it was when I turned on ignition key and below and to the left I believe where the smoke billowed up and crackled . What exactly will fry near the battery case and what is the part called? Is this a fuse or a solonoid?

 

Hopefully if your lucky you only melted the 20 amp thermal circuit breaker that's near the battery (encased in a plastic pouch),and didn't get past that to the cdi,speedo,etc! Plus could have melted the starter solenoid internals that's attached to the battery case? Slice the pouch and see if wires are melted on the square circuit breaker. 3087196 is the number for the starter solenoid(magnetic switch), 2200593 is the number for the replacement circuit breaker if needed! Place the battery back in right and you can temporarily jump the circuit breaker(if need to) to see if you still have power to speedo,starter works,cranks up,etc and no other damage !OPT

 

Will check these parts this evening. So good to get a reply. Thanks Ol Bud! I can only hope what you suggested is burned is all that burned.
Ol Drew