KDXRIDER.NET

can anyone thats converted explain WHY ? benefits? I ride colorado single track, Im 5'10" 180lb and ride as agressive as I can, and My stock shock setup is great on single track and is soft and soaks up almost anything, Feels way better stock than a few KTM's Ive ridden. What are people trying to improve?

I understand upgrading if your jumping and racing mx style but for trails????

kvkdx, there are 15 years of threads on here with people talking about swapping front ends. Happy reading! :-)

Only thing I can tell you about is why I converted over my two KDX's.

I could dial in the stock KDX suspension pretty good for slow technical stuff but it sucked for racing and very spirited rides. Once I get above about 20mph the flex of the 43mm conventional stockers became quite a liability. I can't even count how many times I went off trail at speed and ended up in a tree or cactus all due to fork flex. Hitting rocks, square edges, roots, and whoops you can really feel the stock forks moving when at speed. A more modern USD fork has much less flex which helps keep me on the line I choose. They can also handle G-outs (better resistance to bottoming out without being harsh) and those "oh crap" moments when the ride springs a surprise on you (rocks hidden in sand washes!) way better. Then there is the question of adjustability. Having control of the compression and rebound makes a big difference to me. The stock rear shock is really good but it could be better and that's why I changed to a Showa unit that has a separate high speed compression circuit. It really helps in whoops and braking bumps.

Now, this is all coming from a somewhat aggressive B racer/rider with A speed at times but with C endurance riding/racing in the AZ Sonoran desert.

I split this off into a new thread.

Pretty much copy what SS109 wrote. I thought the stock Forks were fine, especially after putting in correct springs and doing the shim stack mod (search forums). Then I rode another KDX with KX Forks and experienced the difference. Now I ride with '01 KX250 Forks tuned by a pro suspension guy (SR1 in NC). World of difference in almost every aspect but especially as your speed increases. I'm an old C level rider with bursts of B speed (never A) hampered by "D" rider stamina!

SS109 said:
"I can't even count how many times I went off trail at speed and ended up in a tree or cactus all due to fork flex."

The worst injury of my life (which has reduced my strength and caused much pain to this day) occurred about 20 years ago when my stock forks (with gold valves) flexed hitting a squared-edged hole, and spit me off over a cliff. I fell about 30 feet and was stopped when I hit a tree with my mid-section. That injury tore both the SI joints in my lower back. I felt the forks flex a huge amount, and the rebound from that flex is what caused the bike to lose its line. Since that incident, I won't even ride a KDX with stock forks, the first thing I do is install a set of USD forks. The difference to me is night and day, no contest.

Short answer: less flex, more tuneable.

Of course if you never race and only ride slow technical stuff you can likely spring it properly and be happy. Once you start to push beyond those boundaries you'll quickly see the appeal of a fork swap.

on top of everything mentioned you get rid of the massive amount of under hang below the axle.

javjacob wrote: ↑07:21 pm Jan 12 2020 on top of everything mentioned you get rid of the massive amount of under hang below the axle.

Yup! I forgot about that.

Great question. I had been wondering this also. Since so far have just been riding the right slow stuff. Answers all also help a lot, and i feel bad for Gumby. That sounds nasty.

[quote=kvkdx post_id=205389 time=1578678529 user_id=16994]
can anyone thats converted explain WHY ? benefits? I ride colorado single track, Im 5'10" 180lb and ride as agressive as I can, and My stock shock setup is great on single track and is soft and soaks up almost anything, Feels way better stock than a few KTM's Ive ridden. What are people trying to improve?

Try jumping it high and then you will understand. I agree standard is great for doing what it is made for

SS109 wrote: ↑10:33 pm Jan 10 2020 Only thing I can tell you about is why I converted over my two KDX's.

I could dial in the stock KDX suspension pretty good for slow technical stuff but it sucked for racing and very spirited rides. Once I get above about 20mph the flex of the 43mm conventional stockers became quite a liability. I can't even count how many times I went off trail at speed and ended up in a tree or cactus all due to fork flex. Hitting rocks, square edges, roots, and whoops you can really feel the stock forks moving when at speed. A more modern USD fork has much less flex which helps keep me on the line I choose. They can also handle G-outs (better resistance to bottoming out without being harsh) and those "oh crap" moments when the ride springs a surprise on you (rocks hidden in sand washes!) way better. Then there is the question of adjustability. Having control of the compression and rebound makes a big difference to me. The stock rear shock is really good but it could be better and that's why I changed to a Showa unit that has a separate high speed compression circuit. It really helps in whoops and braking bumps.

Now, this is all coming from a somewhat aggressive B racer/rider with A speed at times but with C endurance riding/racing in the AZ Sonoran desert.

Great FEEDBACK, thanks, My friend Dennis KTM guy is your twin, A rider ability and speed, but C endurance, lol, Im slow and technical with B endurance, I love to ride hard colorado single track, but enjoy getting on FLowy single track where we can rail w some speed, SO far the stock stuff is great and I want to spend money making sure fluid/seals/springs are all right and see how that feels, then start dreaming of conversion, I think just new seals etc will be good for colorado, But I love reading about mods and why.

Thanks for responses, Again I ride mostly single track colorado high country, slow gnarly, some flowy curvy, water crossing, High mountain passes, and some quad trails where we open it up a bit, Ive never had issues "hanging up" with my stock forks, I ride thruogh boulder feilds and dont catch, I love the soft, its like the Honda XR250/400 front end, soft and soaks up all the rough stuff, What I love about stock KDX is its soft and soaks up rough stuff, and feels heavy and planted not Light and Jumpy, My honda 250x and EVERY KTM I ride feels light ront and twitchy and I feel Ill kill myself when the front end jumps around and twitches at speed, I always think I could NEVER ride a KTM without a steering stabilizer, but my KDX feels so planted, I LOVE the stock feeling front end, Im obviosuly a minority in this mindset so Ill keep watching and reading, but so far I just need a suspension tune up: valves, fluid, seals etc and I think Im good. thanks for all the smart , thought out comments, KDX baby !!!

If.....If I was gonna swap: You can copy a link If im being lazy as Im sure the convo exist: But WHats the Better option for a front end SWAP that I can use my stock rims, just a bolt up and go???? better choice: ??

(Edited to combine multiple posts)

"You can copy a link If im being lazy as Im sure the convo exist"

...OR, you could use the search function to read 15 years of other people's experiences.

Also, when you mentioned stock rims, do you really mean "wheels"?

Great feedback and thank you all!! I like the soft stock suspension and Im 5'10" 175, now I understand why I like the stock suspension is because Im mainly riding colorado high country single track w obstacles and we are rarley "on the pipe", Yes when I practice or ride w a buddy on the MX track I can feel the too-soft weakness, But this is a rare thing for me to ride, Id rathe rget lost in the colorado backcountry wilderness and Lug this baby around making Ktms and Betas jelly that I can hang yet saved soooo much cash lol !!!

If you're going to spend money on bushings and seals, get some fork covers on there, your seals will thank you.

Hey, kvkdx, that's a really nice looking bike. I like the white. Tell you what, make a donation to this site so you can send/receive PM's and I have a set of fork covers you can have for free. All you have to do is PM me your shipping address. When I get your PM I'll know you've made that donation. No size requirement on the donation. Site doesn't run for free. BTW, sooner or later, probably sooner if you're riding much, you're gonna' have to do something with a worn out kick lever. Take the money you're saving on fork boots and put it into a KX125 kicker conversion. Search the forums for that. Keep on brapping!

Old Guy Racin'

bufftester wrote: ↑09:01 pm Jan 23 2020 If you're going to spend money on bushings and seals, get some fork covers on there, your seals will thank you.

I’ve heard people complain about stiction from seal savers?

Not seal savers, boots, I know lots of folks think they detract from the look, but they do work and help prolong the life of the seals and wipers. Or you could go the route of the 98 RM and run fork guards up top.

I agree with doakley though, you've put together a nice looking bike. Man, if you could find a white rear fender that worked...

kvkdx - If you live near Colorado Springs and we meet up sometime for a ride, I'll let you test out my bike so you can do a side-by-side comparison. I haven't made the conversion yet, but I recently picked up a complete '97 kx250 front end for $150 off of CL. I also got the dude to throw in the $46 kick start boss with the deal so that I can get a kx125 shorty lever installed. I'm having a suspension tuner here in the Springs get things setup for me, and will have it tailored for single track/technical riding.

I am also running a Lectron carb and FMF pipe, along with 607 reeds, and am pretty much the same height/weight as you. Like you, I really enjoy my current setup for single track and technical riding, but when I decided to do a CORCS race with it this past summer, I was bottoming out on pretty much every jump. After doing a bunch of reading on this forum and hearing all of the positive results, I decided it was time to do this swap as well.

Todd