KDXRIDER.NET

i have an 04 200 xr 400 40 springs 10mm of preload clickers set to 18 out race sag set played with rear comp. & rebound but front end is all over in corners this past weekend on a steep rocky rooted uphill with a slight turn 3/4 of the way up when i got to the turn it just folded under on another soft flat turn with a slight berm it just washed out i have brand new maxxis it's on front and rear with 11 lbs on air in each i'm 185 without gear any suggestions to help with handling would be app.

There is an argument for the tires not being up to snuff but this is not the root of your problem.
Try these in this order.... it should solve your problem.

Release built up air in the forks.
Decrease compression damping.
Slide forks tubes up 5 mm.
Lower fork oil level.
Install softer springs.

I don't see it the same way Indawoods does.

Folding over on a uphill turn where the forks should not be heavily weighted and washing out on a bermed flat corner. I would be Increasing my compression damping on the forks an maybe slipping the forks down in the triple trees. (flush with the top of the upper tree.)

I weigh about 15 lbs more than you but otherwise the bikes look to be set-up the same. I would go to 12 clicks out from full hard on the forks and set the rear shock rebound and compression settings to stock settings for starters. If you need more rebound control you will need to go with a heavier oil in the forks. I set up my boy's bike with Mobile I ATF at 100 mm air-gap and it seems to be working fine in these conditions. If you are running real hard you may want to add another click or two into both the forks and shock but I think you should be pretty close.

Hey nykdxer, I'm almost identical to you. 01 200 and I have the same tire and clicker settings, but I weigh 180 with XR 400 springs .382 with 11mm of pre-load. The bike just plain feels squirrely. I finally have gotten so disgusted with the poor handling that I took my forks to my local Racetech rep. I haven't gotten them back yet but when I do I'll let you know how it handles. It will have gold valves and Racetech springs for my weight ( I think .42). Anyway, I will let you know how it helps!

Wow... that's interesting...

I think you both have too much preload for one, but I have no idea what your front sag is...do you?
Also...washing out is a symptom of too much compression, going uphill and folding over could be bad technique...had your weight wrong but can't really comment there without seeing you ride.

Hope you get it sorted out....

i'm running forks even with trees 100mm of oil and mobil 1 atf hey kingsxit please let me know how it works out im ready to do the same thing inda i hear ya about the technique but by my 3rd attempt at the hill the rest of the group was at the top watching or i should say waiting for me and they commented on how the front of the bike just went from under me at the same point and that something must not be right

You say the Maxxis ITs are "brand new"....How did it handle before you put the new IT's on? Did you make any changes before installing the tires? ITs are notorious for "break in time"...and the IT front (for me) tends to wash way more than the Maxxis SI or Pir. MT44 or Metzler MC4 up front.

Also, you describe two very different problems. One: a "fold over" and Two: a "washout". Since these two conditions are typically (all other factors the same) caused by opposite settings, I'd have to agree with the posibiltiy that one of the two were caused by technique. I know of one particular hill climb that I seem to have a similar problem on.

Later
Robb

Inda - Your correct that washing out in flat corners could be a sign of too much compression - It really depends on where it is washing out at. If it is washing out in the first half of the turn then maybe too much compression but if it is washing out the second half of the turn too little rebound dampening.

The reasoning that I used is - Since the forks are "folding over" on a Uphill Section where the forks should not even be significantly loaded would cause me to think it was not too much compression or too much spring. Could be way too low of oil or low compression settings allowing the forks to ride way too low in their stroke. Overall it read to me that the forks were too soft and when they hit the roots in the turn they were diving. Soft forks and weight too far forward (bad technique) would contribute to his woes as would an overal too stiff of shock on the rear of the bike. JMO

nykdxer
if you didn't have this problem before i would suspect the tires,i have used the maxxis tires on my old 87 kdx and had much of the same problems with the front end washing out and after a couple of rides i bought new dunlops i believe i put 756 rear and 742 front i put the same dunlop set up on my 220 also.its just my opinion but the maxxis tires just don't grip good in corners/turns they are also more narrow than the dunlops,kenda,etc..i will never buy another set of maxxis!!

At 185# with .40s and 10mm of preload, he's not too low in the stroke (my WAG).

That said, 'folding under' and 'washing out' are on opposite ends of things to my way of thinking.


Do get a set of fork bleeders. Use 'em often.

Change your preload to 3mm.

Set your oil level to 115 or 120mm.

OEM valving isn't very good. Backing off the compression clickers and letting a good valve do its job is a good idea...if you have a good valve job. You get a much better result from a properly setup valve than pinching off an oil flow orifice (clickers).

Some of what you are having problems with (as I understand your description) is something I've dealt with. I don't have OEM valving...my clickers make a pretty big difference. Still...a couple more clicks out, losing built-up air shock pressure in my forks, dropping 5mm preload and dropping the oil level got me a completely different (and enjoyable) bike.


Everyone has their own point of view...but...Maxxis? Ick!

.42s for a 180# kind'a guy is typical RaceTech point of view.


...don't think much of that, either.

Whatever floats your boat!

thanks for the info looks like im getting a new front tire and possibly a revalve depending on how it goes for kingsxjt

I'll let you know how my boat floats!

I rode wsjkawasaki's '87 KDX200 when it has near new Maxxis IT tires. I think they suck ass to put it politely. They are both narrower than several other front and rear tires I had (of course I measured it, it's me!).

If it makes you feel any better, even the world's best riders stumble over roots. They are difficult to ride on!

"steep rocky rooted uphill with a slight turn 3/4 of the way up"

That sounds like a great place to wreck. Without seeing your technique, it's hard for me to not blame some of it on the tires. Your fork setup sounds good to me.

nvkdxer whats your race and static sag? rear shock

oh and i thought the usable range on kdx's was 16 clicks? i dont wanna look it up im lazy

save your money dont revalve your forks. get kx forks or get a kx.