KDX in Motocross

Joined
Jan 23, 2002
Messages
2
Likes
0
#1
Has anyone had any experience with a KDX on a motocross track, especially one that is made for speed with large jumps. I'm curious because the bike is so good in the woods (I've got an 02 200), and I also enjoy motocross. I'd like to use the same bike for both types of riding and am wondering what mods would suit the bill.
 

Fred T

Mi. Trail Riders
Joined
Mar 23, 2001
Messages
5,272
Likes
2
#2
Chck out DKB's gallery

Click on the "member Gallery" above and look at his pictures and then PM him.

If you mx you might want to stock up on:
frames, rims, hubs, handlebars, collar bones and stuff like that. :uh:
 

70 marlin

Mi. Trail Riders
Joined
Aug 15, 2000
Messages
2,963
Likes
0
#3
she flew like the space shuttle!

only thing that it needed was a better rider!:cool:
 
Joined
Apr 22, 2001
Messages
164
Likes
0
#4
I purchased a used 2000 KDX220 that had been set up for a serious enduro racer, Race Tech had stiffened the suspension, sorry I don't know the details. I use my KDX about 90% MX and have had no problems. I weigh 180 and have no problems with the 50 foot jumps. I previously had a KLX and after 2 broken frames decided to try something different. I am a bit odd but I like the feel of a woods bike so that is what I ride.
 
Joined
May 21, 2001
Messages
90
Likes
0
#6
KIDX, what fender do you have on your KDX. It really looks great. I tried a Circuit on my 92 and it took a lot of modifications. I broke it my first ride after I put in on. I might get another one. thanks Kevin
 

KiDX

Sponsoring Member
Joined
Mar 30, 2001
Messages
406
Likes
0
#7
It's a 93 KX 250 rear fender. It required little to no modification.;)
 
Joined
May 1, 2000
Messages
24
Likes
0
#8
A KDX is completely capable of MX, but that's not what its made for, so you can't expect too much out of it. You'll definately want to improve your suspension, and look into top end/ speed modifications.
 

thorman75

"Team Army"
Member
Joined
Dec 9, 1999
Messages
673
Likes
0
#9
ive seen fredette spank alot of guys on a mx track with his kdx.but thats jeff.it depends on the track too.a natural terrain track like red buds grass race youll do fine.but i couldnt see tryin to do larocco's leap at red buds pro track with a kdx.a cr500af is the ticket there.
 

dkb

Sponsoring Member
Joined
Apr 6, 2000
Messages
93
Likes
0
#10
I had Jeff.F put stiffer springs and re-valve my forks and shock. A rev pipe and 35mm carb. The bike is not the problem for me on a mx track its me:( I watched Jeff fly on the gp and mx track at dirtweek. I used to own a 89 kx 125 (last mxer I had) and this bike with the susp. mods for my weight is just as good if not better. The fork work is the best mod. to do before anything else. My two cents worth
 
Joined
Apr 22, 2001
Messages
164
Likes
0
#12
What you need to do to your suspension depends on your weight and how big the jumps are you plan to tackle. You will probably need stiffer fork and shock springs but here are some near freebies you can try. Replace the stock 5wt fork oil with 7.5wt and turn the clickers several clicks firmer, on the rear the only freebie is adding a bit more pre-load and turning the clicker a bit firmer. My son rides a KDX on a MX track with only these mods and he is fine,but he only weighs 140.
 
Joined
Jan 30, 2002
Messages
25
Likes
0
#13
Thanks Mike,

I weigh 185# so this may not be enough. I'll try it though. Does anyone know specifically which springs I should replace my fork springs with? Should I just use stiffer springs or progressive?

Jimbo
 

thorman75

"Team Army"
Member
Joined
Dec 9, 1999
Messages
673
Likes
0
#14
stay away from the progressive springs.i dont know anyone that could get them to work right(in the forks anyways),i tried them and went back to straight wound.here something you might want to try. race tech makes a 3 way kit.you can have .40kg,.43kg or .46 kg rates.its part number frsp3750k.triple rate kit for conventional 43mm forks:D whoops i see youve got usd forks so this wont work
 
Last edited:

Canadian Dave

Super Power AssClown
Joined
Apr 28, 1999
Messages
1,202
Likes
0
#15
Based on my experience and given your weight I'd suggest looking to a pair of 0.40 to 0.41kg/mm fork springs and retain the stock shock spring. Your best bet however would be to talk to an experienced suspension tuner. You might want to check out MX Tech's new web page or call them directly. They've done the suspension for a number of forum members with good results. You should also talk to Jeff Fredette at Fredette Racing Products. He runs a KDX dedicated shop, likely has more KDX experience than anyone on the planet and has lots of experience in this area.

I haven't heard great things about progressive springs. I wouldn't be surprised if you were willing to dedicate a good deal of time and money experimenting with different rates you'd come up with something that worked well but why not just go with something that's already had all the leg work done for ya.

David