KDX 250 1991 pinging

Discussion specific to the 1991 - 1994 KDX250 sold in the USA
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impellerhead
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KDX 250 1991 pinging

Post by impellerhead »

I have a 1991 KDX 250 that when it gets really warm starts to ping/detonate when giving it full throttle from low rpms. Any ideas ?
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Julien D
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Re: KDX 250 1991 pinging

Post by Julien D »

what octane fuel are you running? Has the head been shaved or anything? Been through the jetting process?
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impellerhead
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Re: KDX 250 1991 pinging

Post by impellerhead »

Not shaved head, larger jetting than original. Highest octane we have on the gas station in Sweden.
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Re: KDX 250 1991 pinging

Post by Julien D »

Check for air leaks. Check also that the timing has not been too far advanced.
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Re: KDX 250 1991 pinging

Post by Jaguar »

pull the needle up one or two notches to enrichen the mixture,
retard the ignition
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impellerhead
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Re: KDX 250 1991 pinging

Post by impellerhead »

I have pulled the needle up and retarded the ignition, No air leaks. I'm starting to think either the ignition is not working as it should when it gets warm or the KIPS not working as it should.
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Re: KDX 250 1991 pinging

Post by david »

Are you sure it isn't overheating


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impellerhead
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Re: KDX 250 1991 pinging

Post by impellerhead »

That was my very first thought so I took apart the water pump to see if there was something wrong there but no.. So i don't think it is overheating.
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KDX 250 1991 pinging

Post by impellerhead »

I hope I am on to something now because I read newer Kawasaki 250:s act precisely like mine do if the pickup coil has to small air gap.
Those bikes has a external sensor though, This is what it looks like on the KDX 250 1991. Would be nice to have a service manual to see
what gap it should have.

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