Ok so I am looking after may friends cfr 450 while he is away to the army. He left his bike at my house I didn't tell him I was going to work on it and I might not just curious. So here is the deal it's a 2004 crf450 with a youoshima pipe the bike is running rough it starts with no idle even if you adjust it antifreeze leaks out the waterpump then it can only ride for about 2mins because it's too hot and it won't start back up untill it cools ive heard it could be the crank bearings or the waterpump but it also seems as though it could be a topend issue