92 KDX200 bogs out when warmed up

[Railinandnailin]

So my 1992 Kdx 200 isn't running right. It will start up first kick, idle good, and then run really good like nothings wrong. After 3-5 minutes of it warming up doing circles around my house it will start to bog out and die. I replaced the ignition coil and spark plug, and cleaned the carb and checked floats. I am unsure if this is an electrical problem or something like reeds. Thanks for any info.

[Flanker]

Since no one has replied yet I will do my best to help you, people on forum say check and clean air filter, clean carb, check float height, condition of needle and seat, check for air leaks, check reeds, repack muffler. Basically go through the intake exhaust system. My bike used to bog it turned out to be the silencer it needed to be repacked, when muffler packing is bad it causes back pressure which messes with what the compression chamber is doing causing loss of power. Also if you would tell us the jetting that might help. I would start with repacking the muffler, then check reeds ( u will most likely need a new gasket once you take them out) cleaning and oiling filter wouldn't hurt. I am betting its the muffler, also you can't repack a stock muffler its if you have an fmf. Sorry if I didn't make any sense or underestimated your knowledge of dirt bikes.

[Railinandnailin]

Since no one has replied yet I will do my best to help you, people on forum say check and clean air filter, clean carb, check float height, condition of needle and seat, check for air leaks, check reeds, repack muffler. Basically go through the intake exhaust system. My bike used to bog it turned out to be the silencer it needed to be repacked, when muffler packing is bad it causes back pressure which messes with what the compression chamber is doing causing loss of power. Also if you would tell us the jetting that might help. I would start with repacking the muffler, then check reeds ( u will most likely need a new gasket once you take them out) cleaning and oiling filter wouldn't hurt. I am betting its the muffler, also you can't repack a stock muffler its if you have an fmf. Sorry if I didn't make any sense or underestimated your knowledge of dirt bikes.

Thanks for giving that info, I understand all of that. Im just making sure you understand that it doesn't bog at any point in rpm until it suddenly bogs and dies after a few minutes. None the less this info will still help me.

[Flanker]

Would be great if you would tell me more about how and when it bogs and/or dies, does it start easy after it dies does it not start at all?
Does it sits there idling then just cuts out or it starts idling higher before it dies or does it only die when you give throttle or are riding, tell me exactly when and how it dies otherwise I'm just guessing at what's wrong. Would be great to know your carb settings, again tell me as much as you can.

[Railinandnailin]

Would be great if you would tell me more about how and when it bogs and/or dies, does it start easy after it dies does it not start at all?
Does it sits there idling then just cuts out or it starts idling higher before it dies or does it only die when you give throttle or are riding, tell me exactly when and how it dies otherwise I'm just guessing at what's wrong. Would be great to know your carb settings, again tell me as much as you can.

Ill let it idle until its warm (just by feeling) then I can hop on it and ride it like normal. No problems, but after a few loops around my house (3-5 minutes) it will either immediately die out or have some hesitation then bog out. Its all stock, stock jetting and the carb has been checked and cleaned. I have a spare carb with bigger jets. Air filter has been cleaned and oiled. I replaced ignition coil to see if that was a problem. It gets good spark. Like I said it will run perfectly then bog out after a little while of riding. Seems like a carb thing but thought its possible of loosing spark when its warm.

[Flanker]

Usually what would cause this is a bad coil, or a lean condition (bog=lean) being lean could be caused by a couple of things first is the carb settings the needle could be to low but since you say its all stock thats definitely not the problem, another thing is that your main jet is clogged when you cleaned your carb did you take it completely apart and spray carb cleaner through every passage? Another problem could be that fuel is not getting to your carb properly the petcock could be clogged letting only a bit of fuel through that would explain why it starts and idles fine but once you start riding it after a couple minutes the fuel in the line runs out and it bogs and dies. Yet another cause of a bog could be an air leak but it shouldn't cause it to die. It might also still be the muffler. So the next thing you should do is take the the fuel line off point it into a cup and turn the fuel on, fuel should come out pretty fast and the stream should be about the diameter of the hose. Then you should try riding it without the muffler ( it will be quite loud). Also blow through the vent hoses coming from the carb to see if they are clogged.

[Railinandnailin]

Usually what would cause this is a bad coil, or a lean condition (bog=lean) being lean could be caused by a couple of things first is the carb settings the needle could be to low but since you say its all stock thats definitely not the problem, another thing is that your main jet is clogged when you cleaned your carb did you take it completely apart and spray carb cleaner through every passage? Another problem could be that fuel is not getting to your carb properly the petcock could be clogged letting only a bit of fuel through that would explain why it starts and idles fine but once you start riding it after a couple minutes the fuel in the line runs out and it bogs and dies. Yet another cause of a bog could be an air leak but it shouldn't cause it to die. It might also still be the muffler. So the next thing you should do is take the the fuel line off point it into a cup and turn the fuel on, fuel should come out pretty fast and the stream should be about the diameter of the hose. Then you should try riding it without the muffler ( it will be quite loud). Also blow through the vent hoses coming from the carb to see if they are clogged.

I know the petcock might be a little whack but it still flows. I did fully take apart the carb and clean but I could always do that again. I will check vent tubes and try the muffler thing. Thanks

[IDRIDR]

We had a snowmobile do this. Turned out to be a bad head gasket.