Hey I have a 2000 scrambler 400. It idles and runs fine, but when i let off the gas it sometimes begins to backfire or it kills the enigne. Any tips? Also how do i know if the oil injection is working?

 

You might want to look into the stator and see if the marks are lined up, timing could be advanced and or retarded.
Using oil? pump is working then

 

Ok well i moved the clip in the carb up a notch and that seemed to help. But now I have another problem. I had a dead battery and never got around to replacing it. So today I hooked up another old battery I had to see if it would hold a charge, but now when I start it up none of my lights work. Any tips?