I have a 98 xr 650 that i ride to school everyday. unfortunatley, it has become a real hassle because it wont start when i get out of class (it sits for about 8 hrs). however, in the morning when i come back to get it, it will crank right up. it is not everyday that it happens, but it is getting more and more common. is it a fuel system problem? seems like it happens more when it is hot outside.....i just dont know. if anyone has any suggestions, I would be very grateful. thanks. b.