After riding my 660 out on the trails, it just died! It would not restart. I realized that it had a little too much oil in it. My little girl towed me back to the trailer with her 110cc China made and proceeded to talk junk. Anyway, after draining some of the oil out, I could never get it to re-fire. I replaced the spark plug with a new one. After a week of just sitting, it fired up and ran like a champ for about 2 minutes. After running, it just stopped running, no ticks, no bangs, no rattles or anything. Now it just turns over and backfires. I was wondering if it could have jumped timing by spinning the woodruff key, if so is there any way that I can figure this out by looking for a certain tell-tell sign?? The one way starter has been replaced by the previous owner. My last and final question is if I have to replace this one way starter and woodruff key, is it something I should tackle myself or take to a service tech? Thanks for your help.