99 kx 250 expansion?

Discussion for swapping a KDX motor in a MX frame...
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99 kx 250 expansion?

Post by Faint333 » 01:27 pm Apr 25 2012

Would a 99 kx 250 expansion chamber work at all for an '03 kdx 220 in a 2002 kx 125 frame?

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99 kx 250 expansion?

Post by KarlP » 06:41 am Apr 27 2012

I'm sure it will work, not sure how well.

You'll have to get it to fit the KDX cylinder and probably add some straight length in doing that. You will likely have to dent it to get around the bottom of the RH radiator.

It'll be kind of a crap shoot whether or not it will end up performing the way you like.

I got very lucky with using a '96 CR250 pipe. It was already dented and banged up. I welded about 2" of KDX pipe to it so it would fit the KDX cylinder. It worked very well for me. Last year I put another big dent in it hitting a stump, now it is not so good.

It is worth trying, in my opinion.
'08 KTM200xc
'99 CR/KDX Hybrid with that RB stuff done to it
KX100 for the boy

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99 kx 250 expansion?

Post by Thack » 04:56 pm Jun 11 2012

If the shape of the pipe fits the frame then you're in luck. You will most definitely have to do some cutting and welding or tack it in place for another welder. Don't be afraid to make the expansion part of the pipe a little smaller.

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