Ok, so while riding at the track today, my bike suddenly sputtered to a halt for no apparent reason. My dad checked everything and it turned out that the problem was that coolant was leaking into the oil. We haven't torn anything down yet but I'm assuming this would be caused by a water pump seal? I just changed the oil in it last night and there was no leaks or coolant in the oil. However, about 3 laps around the track, and my bike came to a halt and would start back up. What should I look for when we tear it down? What all would need replaced to get it running again? It won't start at all currently.