Hi, I bought my first bike a couple of weeks ago. A second hand ZXR-250A '88, although somehow it has the ZXR-250C farrings on it. Anyway it ran perfectly the first week I had it, it had had a minor service the day before I picked it up. Since then things have been getting progressively worse. The bike usually doesn't start and I have to roll start it. I can hear the motor turning over and I don't think it's the battery because there are a few other problems. Today on my way home I pulled up at the lights it stalled about 6 or 7 times, and I had to take it off the side of the road and roll start it a couple of times. Even roll starting the bike is difficult, the bike starts but occasionally just dies immediately. Sometimes I can keep it revving but as soon as I let it idle it will stop. The whole way home I was constantly adjusting the choke trying to get something that worked but I noticed that whilst I had the same choke setting the RPM whilst idling would be different at each set of lights, 6000, 4000, 1500. It wasn't consistently changing either like the bike was heating up or anything (it was warm as the ride home was a decent distance). The strangest issue I've had happen, which happened briefly today and has happened twice in the past is that I go to take off and the bike has absolutely no power. Today I was in first gear and it just wouldn't get above 2500 RPM. The other time I remember what happened, I pulled out of a side street and got up to third but then suddenly no power. Going down to second, and then first had no impact I had to pull over. None of these problems are fuel related as I haven't even had to go on to reserve. Also, I filled up yesterday and problems started occurring when I'd done less than 40 kms. I don't know much about engines in detail but to me it seems like something is wrong in the mix. The bike does need tuning as idling isn't totally steady, it's not too bad though. Anyway it almost seems like the intake valves are getting caught open, is that even possible?. Or, too much air is being put in, which might explain why I have to roll start. I'm going to take the bike around to my brothers in the next day or two and will strip the bike down and pull apart the engine. Does anybody have ideas as to what we should be looking for? Are these common symptoms of a particular problem? Thanks!