KDXRIDER.NET

Hi,

I'm researching front end sag numbers and wondering what spring upgrade is needed.

Here are my stats:
C beginner rider
45 years old
223lbs and 6'1"
25lbs of gear usually
2002 kdx200 with 2006 forks
Current sag with me on the bike is 65
I'm doing South New Jersey single track Enduros for the most part. Mostly dirt with some sand here and there.

I also have a 2002 kdx220 with 2005 kx500 forks on it that I could redirect the effort to if it that makes more sense.

I tried the calculators but was also reading that fork spring stock has become limited.

Thanks,
Roger

Are your forks sagging to much when you ride it? Are you bottoming the forks when you ride? I took my forks in to a shop for a rebuild and was going to get the guy to put in the next stiffest springs because if you read anything about these bikes , they all call for stiffer springs,he refused to do it! He said I would hate how stiff they were.

At 223# plus gear and being an actual C rider (you state beginner, which is not a C rider) I'd be looking at .41 springs. BUT, I'd be looking at rebuilding and tuning the forks and not just "slapping" springs in.
If you are a beginner, rebuild and tune the forks, add new 7.5wt oil and you should be good for a while.

around .46

Very little preload

At 250, you are about two or three steps above what would be normal intended weight of the designers.

Look at spring rates for a YZ250X or YZ250FX, various KTM... NO WAY IN HELL it is close to .35 on the 1995+ KDX's.

6 Riders wrote:At 223# plus gear and being an actual C rider (you state beginner, which is not a C rider) I'd be looking at .41 springs. BUT, I'd be looking at rebuilding and tuning the forks and not just "slapping" springs in.
If you are a beginner, rebuild and tune the forks, add new 7.5wt oil and you should be good for a while.

I am a beginner rider for enduros. The class they make me enter is C as there isn't a lower class. Apologies if I titled myself poorly but I'm still learning how all the classes work.

FWIW I'm an Expert CCS club road racer but none of that seems to transfer over. lol

I ran .42 springs on my h series kdx. On g-outs in a hare scrambles race I bottomed them out regularly . I'm 200#s with no gear. c rider.

Thank you for the real world experience. I see a good bit of folks on here with too soft springs. How many people have we seen that said OOPS, I knew immediately I had gone too stiff on spring rate for the stock forks.

Jason wrote:around .46

Very little preload

At 250, you are about two or three steps above what would be normal intended weight of the designers.

Look at spring rates for a YZ250X or YZ250FX, various KTM... NO WAY IN HELL it is close to .35 on the 1995+ KDX's.

What shock spring do you recommend?

5.5 or 5.6 should be about right

Jason wrote:5.5 or 5.6 should be about right

Awesome thanks!

I just measured sag on my kdx220 w/ 2002 kx500 forks and it was 85mm. I was reading around and saw a desired target was 55-65? Does that sound right? I don't know what springs are in these forks (.40?) but would .46 springs be the way to go with these forks as well?

Sorry to jump between bikes...

Yes, 65 mm sag is good for the front in woods. 100 mm in the back. Different forks on the same bike won't change spring rate.

Jason wrote:Yes, 65 mm sag is good for the front in woods. 100 mm in the back. Different forks on the same bike won't change spring rate.

Where do you guys like to buy springs from?

Which springs are for KX500, 4147's??

If you want them the next day don't think you will get them cheap. Choose speed or price, not both. f it were me,

http://www.ebay.com/itm/Race-Tech-Fork- ... H0&vxp=mtr

http://www.ebay.com/itm/Race-Tech-5-6KG ... aI&vxp=mtr

I have bought several things from them on their site. Not the quickest, but very inexpensive and they do a good job.

If you are OK with used, you might find some used springs, buy be aware that not every seller knows what they are selling. I looked on eBay and found two that were not what they said they were (wrong color or markings).

Jason wrote:Which springs are for KX500, 4147's??

If you want them the next day don't think you will get them cheap. Choose speed or price, not both. f it were me,

http://www.ebay.com/itm/Race-Tech-Fork- ... H0&vxp=mtr

http://www.ebay.com/itm/Race-Tech-5-6KG ... aI&vxp=mtr

I have bought several things from them on their site. Not the quickest, but very inexpensive and they do a good job.

If you are OK with used, you might find some used springs, buy be aware that not every seller knows what they are selling. I looked on eBay and found two that were not what they said they were (wrong color or markings).

I ordered them. Thanks.

While I have the kx500 forks apart is there anything you recommend doing?

You are welcome. You can try to sell the stock springs to compensate. The shock spring in stock version is 5.0. If someone has a 1989 - 1994 KDX200, it is two steps stiffer for a heavier rider. It is also one step stiffer for a KDX250.

Well, they don't have to be very apart to change springs. Seal / bushing condition is one area. I would normally say revalve the base valve (compression adjuster assembly valving), but at your riding weight, it will compensate some. It could use a little fine tuning, but it would be up to you.

Jason wrote:You are welcome. You can try to sell the stock springs to compensate. The shock spring in stock version is 5.0. If someone has a 1989 - 1994 KDX200, it is two steps stiffer for a heavier rider. It is also one step stiffer for a KDX250.

Well, they don't have to be very apart to change springs. Seal / bushing condition is one area. I would normally say revalve the base valve (compression adjuster assembly valving), but at your riding weight, it will compensate some. It could use a little fine tuning, but it would be up to you.

I received the 5.6 rear spring today and when I get it to 100mm of sag while standing, my free sag number is 22mm. I was reading it should be 30-40mm. Is it more important to aim for 100 or 30-40?

Thanks!

Were you in full gear? It should be a little more sag than that.

Jason wrote:Were you in full gear? It should be a little more sag than that.

I threw 30 pounds of weights in a book bag. If I sit it's 105mm of sag.

I would go with the seated measurement.

Jason wrote:I would go with the seated measurement.

Spoke to race tech and they said they want me to bump to 6.0 with 8mm of preload to hit my numbers correctly. Will keep you posted.