2000 kdx220 best usd fork option

[draelas]

i have a 2000 kdx220. Whats my best option for a modern usd fork swap? Hopefully something thats a simple swap? Something i can do with hopefully a basic set of tools. I see most people go with something off a kx, but seems to require some machining of some kind., but depends on the year and model. What woukd my best option be?

[David_L6]

http://kdxrider.net/forums/viewforum.php?f=104&sid=19977f14425bfeecee9a8c972617b537

[juliend]

The "best" option for a direct fit would be a complete kx500 front end. Forks, triples, and front wheel. You can use the KDX caliper. This does not require any stem swap or machining. KX125/250 and pretty much any other front end is usable if you press the KDX stem out of the KDX lower triple, and press it into the donor front ends lower triple. Not very difficult.

Edited April 9, 2012 by juliend

[Slick_Nick]

If you want to keep your KDX wheel and trip meter etc, I did the KLX300 front end swap. You'll need to respring though if you weigh more than 140lbs.

[94cr rider]

i got a cr125 set up if you want it you can have it for a 100 its got the tripple trees to

[SPUTTER]

The KX500 is the simplest, but the forks aren't the best - even if you carefully revalve the valve stack they are fairly rough off-road in most tough situations.

The open-chambered yamaha forks (pre-2005) are easily tuned for off-road and depending on your weight/aggressiveness you can use different years to get the right spring set for you. I currently have 2 kdx's with yamaha usd's and each is tuned for different kinds of riding. My 200 uses 02 yz125 forks with the stock .41 forks for more aggressive riding, and my 220 uses 04 YZ250F forks with .39's for rough single track stuff. I think the yamaha forks are more easily tuned for off-road than the KX's as the yamaha compression stack base has more flow capability.

The yamahas are an easy conversion. You will need to knurl the stock KDX stem a few thousanths to get a press fit in the yamaha triples (just like you would with most KX triples). The KDX caliper will work, but you will need the yamaha caliper mount bracket. The yamaha fork guards have plastic brake line guides which I use to clamp the brake line to with mini hose clamps. You will also need to widen the KDX stops by simply welding a wider bracket right on the top of the old kdx bracket. I recommend the 2001 and later forks as the triples move the handle bars about 1/2" further forward than the original kdx location, which makes the bike handle soooo much better.

I use a yamaha wheel on one bike and a KX wheel on the other - if you use a KX wheel you'll need to custom make the spacers. Pre-2001 yamaha wheels use a smaller diameter brake rotor so they won't work as is.

Edited April 14, 2012 by SPUTTER

[draelas]

ok thx for the tips... how does one get the kdx stem.."knurled"?

dont suppose someone knows of a howto for swapping forks in this way?

[SPUTTER]

knurling is a machine shop method of expanding the metal - like the handle of some tools. I do my own, but any machine shop can press out the stems from both the "new" triples and the kdx triples, check the relative diameters, knurl the kdx stem if necessary, and then press the kdx stem into the "new" triples.

The whole thing shouldn't cost more than about 50 bucks, I would think.

[Jeekinz]

I think the yamaha forks are more easily tuned for off-road than the KX's as the yamaha compression stack base has more flow capability.

Besides the stack, what is different internally from the YZ to KX's? Aren't they both 46mm KYB's? I never had any luck with the Kawasaki KYB's but I have a bone stock 02 YZ125 that feels great.

[SPUTTER]

Besides the stack, what is different internally from the YZ to KX's? Aren't they both 46mm KYB's? I never had any luck with the Kawasaki KYB's but I have a bone stock 02 YZ125 that feels great.

As far as I can tell the stack, actually more specifically, the base valve itself, is the real difference performance-wise. I had set up a KDX with KX500 forks and I couldn't get the smooth off-road action I wanted no matter what I did with the valving shims. So, I stuck in a set of 04 YZ250F valves that I had (also re-shimmed), and immediately got rid of the harsh hits that were beating me up - so the KX forks were OK other than the stack ass'y. Basically, thats what race tech's gold valves do - allow more flow beyond the shimming end of it. Comparing the KX base valve to the YZ base valves, the YZ valves have larger porting and an additional lower port. The WRF base valves have even more flow - quite a bit more - I'm setting that up for my 220 for rock gardens.

I have never taken apart the cartridges at the same time to compare the yamaha KYB's to the Kawi KYB's so I don't know if the internal valving is different there.

[auriian]

50 bucks at a macheen shop.. thats about what it costs to open the door and talk to you...  😉