Hey everyone, i know that this is a cbr forum but i also have a 06 ninja 250 that just wont cooperate. i was about 5 miles from home when it all started. everything was fine at first, then the bike has trouble at 5-7 thousand rpm and starts to bog and make a choking noise. I dont know if there are iridium plugs in it or not and if thats even the issue. I dont know if the timing is off or what but it could be anything. Its only at 5-7 thousand rpm and it wont go past 7 at all now so it sucks and i really need advice. thanks so much to all that help
--Jake

plugs aren't the issue if it runs under 6k. Does is run well under 6k? Does your dash flicker at all? If not I would look at fuel related issues first... pump, fuel lines, vacuum hoses... whatever your bike has. Run with the gas cap open as well, see if that does anything.

Yeah true, when I had plug problems, you could feel it missing under 7k.

Can you describe the "bog" and "choking noise?" Is it coming from the engine, the air duct, the exhaust, is it low, high, etc etc etc

thanx for your help man. at 5-7k it like loads up and feels like the ignition is retarted. no smoke out of the exhaust or leaks. you can hear it through the exhaust