00 stock ex engine question

[Jcrew2]

Hey guys, before I tear into this thing I wanted to see if anyone had any thoughts on what is going on. I was having a hard time keeping it running until it just would no longer start. I pull started it and it ran for about 30 seconds and that was all she wrote. Now the starter just spins when I try to start it and when trying to pull start it same thing no compression at all it just spins. I have had trouble finding anyone who has posted with the same issue so I thought I would see if anyone had any thoughts, am I looking at a top end rebuild or the whole thing. I love my bike so will definatly rebuild, it will be a good winter project.

Thanks all!

[WwsivicwW]

it can be so many different things.. timing, lack of compression, valves out of spec and the list goes on... if its an oil burner, a top end rebuild is a good place to start..