KX/KDX hybrid build

Bike Builds and rebuilds. Post pics and discuss your projects.
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Joined: Fri Dec 20, 2019 5:49 pm

KX/KDX hybrid build

Post by D17racer » Mon Nov 23, 2020 1:00 pm

Thank you for allowing me to share my build here. I know it doesn’t exactly fit the mould with all the big k5 powerhouses, but I think a worthy endeavor. I’m a 30B vet racer in Iowa/Illinois (Jeff Fredette territory) and mostly compete in harescrambles, enduros, and some GP races. I stumbled across this accidentally, and could not resist the opportunity to build. I’m starting with a 2004 kx125, and transplanting a 2000 kdx220 engine into it. I think the lightweight and nimble 125 chassis paired with the torque and grunt (plus 6 speed trans) of the 220 will make a fantastic and competitive Vet class enduro/harescramble bike. Enough with the rambling here are some photos of what I’m starting with.
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Posts: 2
Joined: Fri Dec 20, 2019 5:49 pm

Re: KX/KDX hybrid build

Post by D17racer » Mon Nov 23, 2020 1:03 pm

After getting the bike mostly stripped I had to clearance the swing arm to fit around the wider kdx engine. I will also need to shorten the inner collars for the swingarm bearings. Once this is completed I can get the 220 engine into the chassis and fab up some engine mounts.
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Re: KX/KDX hybrid build

Post by Sandblaster » Mon Nov 23, 2020 3:30 pm

I've heard of other 200 to 125 transplants but never knew what all was involved.
It looks like a cool project.
Do you know the weight difference?
My guess is about 4lb :D
Please keep sharing your progress...
If bikes are for kids I'll never grow up.

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