Kdx 250sr

Discussion specific to KDX models not sold in the USA
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Dan 250sr
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Kdx 250sr

Post by Dan 250sr » 08:11 am Nov 11 2018

Has anyone ever tried to modify the cdi on a sr version. Stator wires go through a rectifier then to the cdi on my bike Japanese version... European kdx seem run straight of the stator to cdi . I have a kx 250 cdi , could this be wired in ? Be great to know if possible thanks...Image

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Dan 250sr
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Re: Kdx 250sr

Post by Dan 250sr » 06:56 pm Nov 11 2018

Dan 250sr wrote:Has anyone ever tried to modify the cdi on a sr version. Stator wires go through a rectifier then to the cdi on my bike Japanese version... European kdx seem run straight of the stator to cdi . I have a kx 250 cdi , could this be wired in ? Be great to know if possible thanks...Image

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Kdx 250sr wiring diagram apparently , other one is for kx. Would it be possible to wire kx cdi to kdx ? Be great if anyone could help. Thanks ImageImage

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bufftester
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Re: Kdx 250sr

Post by bufftester » 07:23 pm Nov 11 2018

Can't read the SR diagram, but if the ignition and lighting circuits are separate like they usually are chance that you could use the KX CDI and coil in place of the SR units. That's assuming the SR has a similarly wired stator. Of course the curves will be for a KX powerband so you may lose some performance there. Is there a particular problem with your current unit?

Dan 250sr
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Re: Kdx 250sr

Post by Dan 250sr » 10:16 am Nov 12 2018

bufftester wrote:Can't read the SR diagram, but if the ignition and lighting circuits are separate like they usually are chance that you could use the KX CDI and coil in place of the SR units. That's assuming the SR has a similarly wired stator. Of course the curves will be for a KX powerband so you may lose some performance there. Is there a particular problem with your current unit?
Ok I'll look into that. I know the sr goes to rectifier then cdi. I have fitted a 1988 kx barrel con rod and piston, with center power valve, I couldn't get sr piston. I just know it's got more to give at top end. Pulling like a train bottom end. And from what I can make out the sr cdi is slightly down rated? Thanks for input I hate electrics...

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Dan 250sr
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Re: Kdx 250sr

Post by Dan 250sr » 07:27 am Jan 26 2019

Seems like a kx cdi uses one of the coils for timing curve...has a smaller coil.. also kx stator wires go straight to cdi.. kdx goes to rectifier/ regulator then back through to cdi. I'm having trouble getting my head around this timing curve voltage.. kdx puts out same voltage through all 3 stator wires

Stevetooms
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Re: Kdx 250sr

Post by Stevetooms » 08:16 pm Nov 24 2019

Did you manage to get the kx250 CDI to work on your kdx250 pal

Dan 250sr
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Re: Kdx 250sr

Post by Dan 250sr » 08:25 am Dec 22 2019

Hello sorry just seen message, no I kind of gave up as my stator isn't compatible with that cdi, from what I can make out you need a signal to make timing curve work, the kx uses the smaller coil for that from what I can see

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Re: Kdx 250sr

Post by kdxsully » 08:39 am Dec 22 2019

Probably has an exciter coil, right?
I like turtles

Dan 250sr
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Re: Kdx 250sr

Post by Dan 250sr » 05:05 pm Dec 22 2019

From what I can make out it uses the smaller coil on a kx to adjust timing curve, kdx 250 sr coil is completely different... I think the smaller kx just makes more voltage as revs get higher and that's how it changes timing.. stand to be corrected on that...

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