90 kdx 200 / kx 500 motor swap help ?

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Ca94cr250
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90 kdx 200 / kx 500 motor swap help ?

Post by Ca94cr250 »

I'm a veteran kx 500 mxer and just got a great deal on this 1990 kdx 200 that had the motor was torn apart . Ive also built a few choppers and am decent when it comes to fab work . I really want to cram a 500 motor in it , just curious if it's been done ? If so how severely will I have to chop the frame ? Thanks !
sarrant
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90 kdx 200 / kx 500 motor swap help ?

Post by sarrant »

Not sure I get it. The strong suit of the 90 KDX definitely isn't the suspension nor the frame. It's a really close cousin of the KX500 chassis, with a cheaper fork. If you look around here (especially in the hybrid section), you'll see the common shift is to try to stuff KDX motors into more modern MX chassis.

Granted, it's pretty tough to beat the KDX's short wheelbase once stuff gets super slow and gnarly, but that's probably the spot where a KX500 motor would shine the least.
Ca94cr250
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Ca94cr250 »

I'm with you on that , this is eventually going to be a supermoto and enduro , just an all around fun bike . I'm still contemplating doing a full rebuild on the 200 motor and putting it back in . I'll admit though , I was sketchy about the smaller displacement . I've read so many people talk about how smooth and on point these motors are . I have not had the pleasure of riding one . I've ridden plenty of 125cc and 250cc though . Which one do you think it's closer to power wise ?
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Sullyfam
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Sullyfam »

I bought my son a 2005 kdx200 and it is a blast to ride. In fact I am selling my RMZ450 and to picking up a yz250 tomorrow, so I will be able to chime in on how the 200 compares to the 250. While the displacement is close I honestly don't expect them to be similar in feel. Purpose built trail bike with soft/dated suspension versus MXer with reasonably modern suspension. Still it will be fun to compare!


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Ca94cr250
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90 kdx 200 / kx 500 motor swap help ?

Post by Ca94cr250 »

Very nice ! Please update me on that ! I'm in the process of doing a complete front end suspension , wheel and brake swap from a 97 kx 125 , so hopefully it will be up to par as far as the suspension goes . I already rebuilt the rear shock which I hope will be sufficient? I wouldn't expect the 200 to hit as hard as the yz250 , but with the carb and head mod I wouldn't think it would be to awfully far off (power wise ) keep me updated please !
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Sullyfam
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Sullyfam »

Plan to ride Monday and will post an update. Here is my new pumpkin eater!
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Ca94cr250
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Ca94cr250 »

Very nice ! Have fun and update us !
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90 kdx 200 / kx 500 motor swap help ?

Post by ohgood »

Ca94cr250 wrote:I'm a veteran kx 500 mxer and just got a great deal on this 1990 kdx 200 that had the motor was torn apart . Ive also built a few choppers and am decent when it comes to fab work . I really want to cram a 500 motor in it , just curious if it's been done ? If so how severely will I have to chop the frame ? Thanks !


interesting combination you're thinking about here. as a veteran, you'll have more insight than my 20 minutes of STUPID fun on a kx500 supermoto, but here it is anyway:


kdx200- good lord what a woods bike. fantastic handling, wonderful engine, smoooooth predictable power. i've had street tires on it for about a heartbeat, and realized it was a WOODS bike, not a drz. i own a drz, but it's my street bike now ;-)


the kx500--- is a redonkulous supermoto. if you are the kind of guy that can handle a kx500, cr500, kx450 (or similar) with street slicks, go for it. but don't waste your time with putting a kx500 jug in a kdx frame. i wouldn't anyway. it's SOOO much power, that will never be realized on a trail that the kdx's suspension can keep up with. maybe with a rekluse, but mannn, that's $$money$$ just to tame the beast and make it tractable.

i'd say make the kdx engine live again, and use that kx engine like it's meant to be: RIPPING and ROARING, not squeazing between trees so tight they creak when the wind blows ;-)


anyway, call me a fool or whatever, just please update us with what your plans turn out to be. i wanna see it.

:)
Ca94cr250
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Ca94cr250 »

Very good insight buddy .. That's the conclusion I came to also . I appreciate all the insight !
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Actionman »

I traded my 02 200 to a 97 rm250 because I thought I wanted more power. I was way wrong. The kdx200 is the king of the trails. It was all the bike I could've ever needed but I didn't know it at the time. Now I realize it and I can't afford to buy another one. Boo!
2002 KDX 200
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diymirage
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by diymirage »

Actionman wrote:I traded my 02 200 to a 97 rm250 because I thought I wanted more power. I was way wrong. The kdx200 is the king of the trails. It was all the bike I could've ever needed but I didn't know it at the time. Now I realize it and I can't afford to buy another one. Boo!

where are you located ?

I have both a 200 and a 220 for sale in Michigan...reasonably priced

http://holland.craigslist.org/mcy/4698093031.html
newbbewb wrote:DIYmirage has it right.


-1996 KDX 200 woods weapon (converted to 99 green body)
-1996 KDX 200 plated street toy (barney edition)
-2003 Yamaha TTR125-L (wifeys bike)
-1997 KDX 220 project bike
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Sullyfam
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Re: 90 kdx 200 / kx 500 motor swap help ?

Post by Sullyfam »

Update as requested - Just spent the day riding the yz 250 and there really is no comparing it to the kdx200. I would not expect the two to be similar, but it's really night and day. The yz is much more powerful and handles far superior for my riding habits. However, this is also not surprising given the vast difference between the two. The yz is set up nicely for trails so much of the MX hit has been muted this launching into the woods is not a concern. That said, I wouldn't trade the KDX for anything. Super fun and never gets away from you. A perfect bike for my son and me for when I want to really feel like a kid again! So win win in my book!

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