Should I change the front springs in our KDX's ?

[NCFRC]

My son and I both have a KDX , an 05 220R and a 06 200 .

Should I even think about changing or modifying the front springs for mildly aggressive trail riding ?

Thanks for any feedback,,,,,,, and sorry I couldn't find this posted but I'm sure it has somewhere.

 

[dansavage]

In my opinion, yes, assuming your weight exceeds what is recommended for the stock springs. I bought a heavier set from fredette, they made a big improvement in how it handles in the woods.

 

[glad2ride]

WOW!! A 2005 KDX220R AND!! a 2006 KDX200. You are the MAN! (yes, I am being honest, not a smartypants.)

Changing the fork springs is a very common modification. Pretty much everyone who has done it, wishes they had done it sooner, or that they think it is great.

 

[NCFRC]

How stiff did you go on the springs ?

The stock ones are .35 's

 

[glad2ride]

Look on the www.mx-tech.com website and put your information in their spring rate calculator. Be sure to list your weight with all your riding gear on, including any water backpack, extra tools, etc. that you might carry.

They list the stock springs as the correct rate (stiffness, if you will) for a 95 pound fully geared rider. :-)

 

[jawx]

yea thats crazy. I just tried that link and I learned alot. It recommends .44 front springs for me.. I weight around 200 with gear. Thats a big jump from the stockers. Where can I buy these springs and whats an approximate price?

 

[glad2ride]

MX Tech has some. Race Tech has some. I am not sure if FRP Offroad carries .44 or not. Normally, a pair of fork springs or a shock spring is $110, plus shipping.

 

[NCFRC]

I know this sounds hoaky , but someone else commented about adding a 1" spacer to the stock springs ??

Any comments on this , I'm guessing PVC pipe.

 

[fusion]

I know this sounds hoaky , but someone else commented about adding a 1" spacer to the stock springs ??

Any comments on this , I'm guessing PVC pipe.

ya that would work, i bought race tech springs for my CBR and it came with two metal pipes to fine tune the suspension and my KDX came with a 3 inch long PVC pipe in it and it seem to work great.

 

[mudpack]

I know this sounds hoaky , but someone else commented about adding a 1" spacer to the stock springs ??
Any comments on this , I'm guessing PVC pipe.

That would increase the preload, making the initial travel stiffer. Better to increase the spring rate, which would give you a soft intitial travel but with more resistance to bottoming.
Springs make better springs than PVC pipe does.

I just received a set of heavier fork springs from FRP, along with a lighter shock spring. (Fredette has some recommendations on spring rates on his website, too)
The Fork springs came with a 6" length of PVC pipe!!! I hope Jeff doesn't think I'm going to put THAT in my forks.... :rotfl:

 

[glad2ride]

NCFRC, that isn't going to work. Only the correct rate spring will make up for not having the correct rate spring. Spacers only put preload on the springs, they don't change the rate of the spring, which is the problem. The springs already have too much preload on them, already.

mudpack, the PVC pipe is cut to the proper length to give the springs the correct amount of preload. A lot of aftermarker springs come with PVC pipe in the packaging. Race Tech and Eibach do. Sprigns for USD forks are usally a set length and only a few washers are used, if any. The conventional springs fit so many different bikes that they use the PVC pipe to make up the difference in various bikes. Cut it to where you have 10mm of preload on the springs and you will be fine.

 

[longtime coming]

search "xr400" springs in here and get some that don't require spacers? I put the .38s in mine. Should have gone to the .....671 part #, not the ....761 part #, although they are still a huge improvement over stock. I think JF recommends '38's for me (185lbs). Everyone else suggests stiffer. I should have gone slightly stiffer, but I'm still pretty happy now. The front doesn't dive and wallow nearly as badly as stock, yet is still pretty compliant over little hits.

 

[longtime coming]

Oh, and short answer to the "should I change springs" question is YES!. No matter what riding you do.

 

[NCFRC]

Thanks for the feedback , I'm 197 w/o gear and will probably try a set of 40's or 42's.

 

[NCFRC]

I just ordered a set of FRP .42's ,, just hope their not too firm for the rocks and roots here in northern New England.