My buddy just bought a USED 99 YZ400F. Well, we take it out this weekend, and it starts up fine, so, we start riding around in our field and he says it keeps bogging when hes on the throttle. Well, after riding it for a few minutes, it stalls. Check to make sure there is gas, petcock is on, everything that we can see is fine, oil.. everything fluids wise. Well, we goto kick start it, and we can pretty much jump on it, and its not moving (The kickstarter, that is.) And as far as the decomp. lever, well, we took it off, becuase the guy we bought it from, said we didnt need to use it. So Im assuming he put auto decomp. cams in it before we got ahold of it. And prior to that, its always started fine. My only thing is, is that it wont even bump start either. So not only is the kickstarter like, stuck, it wont bump start either. Any ideas? Suggestions? things I could check and maybe that would be the problem?.. THANKS!!!!