My 2007 Trail Boss 330 starting misfiring a few days ago. I was riding and went to turn the headlights on while on a hill and accidentally hit the off switch and it backfired. It starting misfiring immediately after turning it on and continuing up the hill. Now it only seems to happen when going uphill or on rough terrain. I rode it today for 2 hours without a problem and then it started missing on the way home. Yesterday I changed the oil, oil filter, air filter and spark plug. Can this be from a dying battery or more likely a fuel problem? I currently run 93 octane and use the fuel within 2 weeks.