We just bought a 2008 700 rhino. It started fine when we went to get it and drove around a bit on day one. Now it won’t start we put in a new spark plug and while we charged the battery all day yesterday today it was only at 25%. When we charged the battery yesterday it would start but today it won’t even when charging the battery. When we try to start it if you press the gas it stops trying to turn over. Also it back fires every now and then. Any ideas?? My husband can fix anything when he knows what the issue is but he doesn’t have much experience with atvs, more bikes.