KX Conversion Rotor Alignment

[cyclebradd88]

I am almost finished with a KX fork conversion on my KDX200. I am using my KDX front wheel and axle, with a KX Caliper ( because the KX fork uses a different hole spacing for the mounting.) Anyway, the issue is this…
How do I determine the correct alignment between the brake rotor and the caliper? It looks as though one pad is stationary, and the dual pistons move the other pad. Do I space the wheel to narrowly miss the stationary pad? Do I center the Rotor between the two pads when the caliper is completely open? I will appreciate your input.

 

[canyncarvr]

Your KDX axle fits the KX forks?

Not that I've ever found. You can have an axle made (you know...from your local CNC buddy down the street?) that will allow the KDX wheel to be used with a KX fork. That's been done.

The KDX caliper fits on the KX fork. The comment, ' (because the KX fork uses a different hole spacing for the mounting)' is curious. The brake line routing (banjo angle) is different, but the caliper itself is not.

The answer to your question (for whatever reasons you ask it): Center the rotor in/to the caliper.

Something to think about...if one pad was stationary, as the pads wore the 'center' of the pads would also move. That would work exceedingly poorly, 'eh! ;)

Good luck. Methinks you will need some!

 

[Rich Rohrich]

You have to start by centering the wheel in the forks. If you want it to steer peoperly, a centered wheel is a pre-requisite.

To get the caliper spaced properly tape a .060"-.100" piece of welding wire to the outer perimeter of the disc. This will give you adequate caliper spacing above the disc when you lay the cailper on the disc.

To get the caliper centered side to side, fill it with fluid connect it the a master cylinder and apply the brakes (or you can use an air fitting attached to the brake line mount) . The caliper is self-centering on the pins when pressure is applied.

Now you should have correct caliper spacing above the disc, and correct centered placement side to side on the disc.

From here you should be able to see the relationship between the rotor, caliper mounting points and the fork leg as well as how to make them all fit best.

Jewel Hendricks ( MTNE ) taught us that method about 30 years ago and it still works great today. :cool:

 

[canyncarvr]

That's great for whatever caliper to whatever wheel. Likely an error on my part, but I'm assuming some things...like this isn't a rotor diameter that is different from OEM.

No 'assuming' is ever a good thing.

The whole idea of a KDX wheel on a KX fork (without some special parts) is problematic at best. With such a mis-match of parts, best approach caliper mounting/centering from the beginning. My post didn't at all do that.

Thanks!

 

[canyncarvr]

How did the KDX axle/wheel-to-KX fork fit come out for you?

Just curious.......inquiring minds wanna know and all that......

Cheers!

 

[Lumpyboy]

well, I found it easier to buy a KX front end all of the same year (2002) and just use the KDX caliper, even though I have the KX caliper as well and probably should use it. I thought that others have used the KDX wheel, and Fredette Racing also told me I could do it with some bushings/spacers. A fellow named FLBusa on here I believe did that (w/ pics: http://dirtrider.net/forums3/showthread.php?t=94422&highlight=kx+kdx+fork). Anyway, doesn't it all come down to the year of your KDX and the year of your KX forks? I suppose there could be a mismatch under certain circumstances but for more recent year models I also didn't think that was the case.

 

[canyncarvr]

The question was for AZ B.

Others HAVE used the KDX wheel, but with a custom axle. Maybe there is some application for a KDX wheel-KX fork. I don't know what that would be...hence the question. Regarding 'more recent' models..an 'H' KDX wheel won't fit on 46 or 48 KX KYBs that I know of.

I did modify a '92 KX wheel to fit a '99 KX fork..but that's a different issue.

Certainly it's easier to get everything that fits together to start with. There isn't much that cannot be 'redesigned' to work/fit if you're up to it.