Ok. so here it goes. I got a 91 Kawasaki Mojave 250 last week. The guy I bought it from said it needed a clutch. took apart the clutch and everything was well within the wear specs. So I put it back together and started it up and drove it. Now I see why he thought the clutch was slipping, it is fine at low rpm's but once I try to rev it above about 1 to 1 throttle it bogs out and misses and just doesn't want to go. It does this in gear and in neutral. I check the timing and it's dead on, I checked the carb for and intake boot for cracks and there were none. The air filter is almost brand new. What else could cause this. Also the machine is 100% stock.