Kx parts on kdx

[nfisher87]

Few questions:
Will a kx250 carb from a 97 match up with the boots on the kdx, if nto is it possible to get different boots? I figure if kx125's have such large carbs I should def get an increase in power for cheap.

Also, will a 97 kdx front brake fit on 97 kx250 forks? and are the front end conversions reliable?

 

[NSPHIL]

The 97 KDX front brake will bolt right up to the 97 KX forks. The conversion is the best mod as far as handling is concerned providing all fork componenets are in good shape. I do believe your KDX stem may require knurlng to fit the triple tree, but I could be wrong.

 

[adam728]

The 97 KX250 carb is a 38 mm, too large for a KDX. It won't fit the boot, and even if it did, you'd lose a ton of low end power. The 200 simply doesn't inhale enough air or rev high enough to require a carb that size. Plus I believe the 97 KX used a powerjet carb, which seems to me would be difficult to setup (although I do not know what is involved). 125's use the same size carb as a KDX200 because the 125's run at much, much higher rpms. So even though displacement is much smaller, they end up pulling air at relativly the same velocity through the carb.

If you had some extreme porting done and wanted a very peaky KDX than a 38mm carb could work out fo you. But on a stock or even moderately modified KDX that's just too much carb!

 

[apb]

Yeah, I second what Adam said -- you'd lose all low end power, even if you got some boots to fit it. For the record, the '97kx250 carb didn't have the power jet (I believe the '98 got it), as I've got the '97 kx carb on my rmx.

 

[canyncarvr]

If not the most common error in hotrodding, it's sure on the list of the top few....bolting on a way-too-big carb thinking that it's a good thing.

The same applies to any engine.

Carbs are certainly a situation where more is not necessarily better.

re: '...are the front end conversions reliable?'

Yes.

Now there's something off a KX that is well worthwhile putting on a KDX!

 

[nfisher87]

I guess i was getting a little power hungry. If you can't tell I finally am getting around to refreshing my kdx and I'm looking at a lot of different upgrades. soooooooo
NEW QUESTION! yeyy
I've read you have to press the kdx stem into the lower kx triple clamp and sometimes you have to knurl? the triple clamp? what the hell does that mean and how come sometimes, would i have to do this with a triple clamp off a 97? Thanks alot guys this website rocks by the by :aj:

 

[NSPHIL]

IF you HAVE to knurl it is because your KDX stem diameter is too small to fit tightly in the KX lower clamp. The knurling displaces material ( by creating vertical ridges, so you are looking for a vertical knurl pattern) on the stem causing the effective diamter to be larger. The stem is then pressed into the lower clamp. This can take anywhere from 5-15 tons of force to press in. You can have the Inside diameter of the clamp knurled, but the easiest by far is the stem.
There is a chance that you will not require knurling and the KDX stem will press directly into the KX triple tree. I do not recall if the 97 KX to 97 KDX requires knulring, year of your KX to year of KDX matters, they are not all the same.

 

[Yamadad]

If you use a triple clamp from the KX500 (90's vintage), it will bolt right up. No mods necessary.

 

[NSPHIL]

If you use a triple clamp from the KX500 (90's vintage), it will bolt right up. No mods necessary.

Yes, but will the clamps fit the upper fork tubes of the 97 KX?