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2005 KX250F Bog Issue

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When I pull the throttle, the bike immediately bogs as until it dies. its as if I was hitting the kill switch. If I quickly turn the throttle a couple of times before it dies it will rev and the rpms will stay up for a couple of revs, then it will bog again. When I try to ride it idles and when I pull the throttle it wants to die so I have to let off unless I keep turning the throttle like I said previously. Any help? We already checked the jets and they were clean. Thanks in advance for the help!

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you might be jetted to rich for your elevation. or your diaphriam pump is cracked, it squirts fuel into your carb, to release  fuel fast and give you the snappy power from the get go. try a rebuild on your carb :thumbsup: 

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When I pull the throttle, the bike immediately bogs as until it dies. its as if I was hitting the kill switch. If I quickly turn the throttle a couple of times before it dies it will rev and the rpms will stay up for a couple of revs, then it will bog again. When I try to ride it idles and when I pull the throttle it wants to die so I have to let off unless I keep turning the throttle like I said previously. Any help? We already checked the jets and they were clean. Thanks in advance for the help!

Lift up the subframe and with a dead motor watch for the accelerator pump squirt in the bell of the carb.

I'll bet you don't have one.

Usually from corroded carb internals like the pump nozzle.

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you might be jetted to rich for your elevation. or your diaphriam pump is cracked, it squirts fuel into your carb, to release fuel fast and give you the snappy power from the get go. try a rebuild on your carb :thumbsup:

Wrong you are to lean if it bogs, if it is too rich it will crackle and sputter buy not bog like hitting the kill switch!

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No if it is lean it will be hard to start and crackles and sometimes backfires, when it is rich it will bog. Too much fuel is going into the carb at the same time and not enough oxygen so the fuel is not burning right.

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No if it is lean it will be hard to start and crackles and sometimes backfires, when it is rich it will bog. Too much fuel is going into the carb at the same time and not enough oxygen so the fuel is not burning right.

?????

You need to learn about jetting 4S

Pilot and fuel screw - For idle only

Needle: Straight diameter - Just off idle to around 1/4 throttle. Taper/length(clip position id fine adjust) 1/4 throttle to about 7/8ths.

Main - 7/8ths throttle to WOT

AP - Anyime the throttle is opened (adds extra fuel to compensate for the momentary drop in vacuum due to the throttle opeing at low rpm) Leak jet (small bore bikes-used to reduse over all squirt and sensitivity) and Timing(Adjusts when the squirt starts) Rivet length - Adjustst total duration. This is the usual cause of a bog, often a combination of timing not being right and too large a leak jet (Bikes are made for pro racers, which most of the customers, no mattter how wishful, are not)..

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