I recently bought a used 2008 sportsman 800 from a dealer. They offered me a warranty but I denied it. On my first ride I noticed it was sputtering at start up. It was cold and after a few minutes of riding power would kick in. I just thought it was warming up. Then on my third day it started sputtering in the middle of my rides, then the power would come back. Today i left to get gas and it sputtered the whole way and wouldn't go over 20. When I pulled into my driveway it completely died(convenient) and now its completely dead. It seems it has to be electrical because nothing will light up at all, but does that explain the sputtering? Are there any common Sportsman causes for this?