Author Topic: Which KX125 for a KDX hybrid?  (Read 5694 times)

0 Members and 1 Guest are viewing this topic.

Offline Crankn

  • Newbie
  • *
  • Posts: 1
Which KX125 for a KDX hybrid?
« on: April 17, 2015, 12:15:50 AM »
I see that the last 125 that hit the US was the '05 model. I believe it was largely the same as the upgraded '03 model.

The Aussies kept getting them till '08 and was wondering if there was any other upgrades in that time that were worth talking about? Mainly to the frame, suspension and running gear to be precise.

My reasoning for this is I wish to build a KDX/KX hybrid using the 200 powerplant, loved those engines, and am thinking the latest model KX I can find may be the better than the slightly older ones. Orrrr, I might be spending more money on a more current chassis which is the same spec as the older year. If that is the case I may find a good '03 or '05 that is just as good as an '08 for a lot less money.

I have heard the 125/200 conversation is reasonably easy, (compared to a AF conversion which I'm also looking into) and i also know the MX rolling chasis will be a lot better than the KDX frame which dates back to about '95.

So would appreciate any info you have on the 125 updates and your opinion on my project thoughts would be good as well.

Thanks in advance.

Offline umberto

  • Administrator
  • Hero Member
  • *****
  • Posts: 2,484
  • First Ride 02-02-19
Re: Which KX125 for a KDX hybrid?
« Reply #1 on: April 17, 2015, 07:19:12 AM »
I currently own a 2003 KX/KDX hybrid, but also own a 2004 KX 250, 2005 KX 125, and a 2007 KX 250.  Yes, I am in Dirt Bike Buyers Anonymous.   :-D  I think most of the latter years changes were made in the 250.  The 125 didn't change much, and the later year bikes (after the stopped importing them to the US) would have been just repeats as well.  Anything from 2003 and up should work fine for what you want to do.  I would focus more on getting a quality bike for a good price. 

There is an excellent KDX only site called that has a whole section on hybrid builds.  Basically you will need to trim your swingarm a bit, fashion some new motor and head stay mounts, fix your airbox with a plate (to use a KDX boot), and modify your exhaust.  The KDX motor is a lot shorter than a KX, and comes up short of the front motor mounts.  It sounds like a bit of work, but it really isn't that much fabrication.  What you will end up with is a perfect trail riding/enduro machine.  I absolutely love mine, it's a blast to ride and has torque for days.  Have fun and post lots of pics.
Perhaps I have a dirt bike addiction?

03 KX 250/88 KX 525/2017 KX250F - Goliath
17 KX250F/04 KX250
04 KX 250 - Lunchbox's Bike
05 KX 125/144

Offline don46

  • Hero Member
  • *****
  • Posts: 1,140
Re: Which KX125 for a KDX hybrid?
« Reply #2 on: April 17, 2015, 08:42:42 AM »
having only built one, I will tell you what I think, which is probably wrong. I used a 99-02 125 chassis and never really roode the bike, but I know the guy that bought it and he loves it. Newer is always better so if you can find a newer chassis I would go that route, same with the motor use a newer motor or at least the last generation, it will make your lif so much easier when installing the pipe. From my perspective the pipe was the biggest issue, everything else was minor fixes. Fun project and pretty easy to do, you could use the latest generation forks with little effort on an older chassis. I have pictures of the one I built someplace on here
Live today, for tomorrow may never come

Online Foxx4Beaver

  • Hero Member
  • *****
  • Posts: 8,936
  • James Stewart DID NOT invent the scrub!!..JoJo
Re: Which KX125 for a KDX hybrid?
« Reply #3 on: April 17, 2015, 10:17:35 AM »
I have pictures of the one I built someplace on here

something like this...,12866.0.html
Excuse me, ma'am...but you've got extremely nice legs!!!...what time do they open???