2003 KX125 frame

Discussion for swapping a KDX motor in a MX frame...
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jjavaman
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2003 KX125 frame

Post by jjavaman »

Hi boys, I've got a chance to snag a complete 2003 KX125 with a blown motor. How hard is it to swap my 220 motor into that frame? Anybody done one?
97-220 with a PC pipe. 2015- RB carb and head mod
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bufftester
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Re: 2003 KX125 frame

Post by bufftester »

Super easy, yes I did it (2001 frame, but same). You will need to fabricate new engine mounts for the front, trim the swingarm and drill out the swingarm pivot through the engine case to 17mm. I did both in my garage with hand tools and a cheap HF welder. I also cut the hoops off my KDX frame and transferred them over (the case protector ones) but not necessary. The biggest pain was the carb to airbox boot. You can get a kickstand for the 03 as well (pro moto billet) that I couldn't for the 01. Also the 03 was a one off year for the KX125, 99-02 share parts, and 04-05 share parts, but the 03 has a few of its own so keep that in mind. I believe the 03 frame was done by user Biggles on here, and a couple others IIRC.
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Tyl3r
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Re: 2003 KX125 frame

Post by Tyl3r »

Search the hybrid forums.... 03-05 KX seem to the most straightforward to swap. I did an 05 (same thing), and didn't think it was bad. If you've ever done a complete bike rebuild before and you have basic weld/fab skills, its really not that bad. My build thread sucks now because of the photobucket images (but you can click on the failed image it will open the picture in another tab), but you can get the idea: http://www.kdxrider.net/forums/viewtopi ... 11&t=18327
04/05 KX220 Hybrid all decked out
18 KTM 500 EXC-F Dual Sport/Sumo toy
24 KTM 300XC-W Cheater bike
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