Advice on Springs - KX500, 155lb rider

[IridiumRed]

Hey Guys - posted this on Dirtrider.net as well, but hey this IS a KX500!

How accurate are the spring rate calculators?

Just recently got a KX500, 1997.

I'm 5'4, 155, upper beginner/lower intermediate skills

I'd say I'm 90% trails/woods. Maybe one day a motocross track...i'd be slow, but it would be fun

Springs seem too stiff.

I'll probably revalve it here in the near future (do it myself with Racetech), but I know that I need to get the springs right first

Bike came with stock suspension, and a pretty new rear shock (still stock)

Racetech recommended:
Forks .42
Shock 5.0
Since I want to trail/woods ride, i thought i'd go a little lighter on both ends, proportionally of course -

What i installed:
stock fork springs, .40 (according to racetech)
racetech 4.8 shock spring (used, from Ezbay). Right around 4-5% lighter on each end. Filled with oil to about 120mm, racetech 2.5wt. Worked the piston plenty to bleed the air....

But - my sag numbers now -
rear - about 80mm race sag (with all the preload out of the rear), 30mm / more of free sag
front - haven't gotten a good # on this (i dont have a great assistant), but its gotta be around 25mm race sag. they barely move when i sit on it. I'm only 5'4 but can handle the bike pretty well. An extra nearly 1" would certainly make life easier for me though, ESP if it makes the suspension "right"

I dont think i have stiction issues - i completely tore down and greased the rear linkage. Replaced some parts as necessary (used a moose linkage rebuild kit).

Pushing down on the back of the bike and letting it rise up slowly, or lifting on the back and letting it settle, the numbers are really close. So i dont think I have a sticking linkage.

The forks have more stiction, but thats fairly normal. I even assembled the forks w/o springs and put them on the bike, and put the front axle in place and worked the forks up and down as I tightened the triple clamp bolts just to make sure I didn't have somethign out of alignment. The forks stroked nice and smooth, no noticeable binding.

ANYWAYS - I'm thinking of going one step lighter on each end, say .38 and 4.6. I thought that spring rates were MAINLY determined by rider weight/bike, that there wasn't that much "fudge room".

Sorry for the long post, but I'd like to hear if you guys think i'm on the right track, or if there is something I perhaps overlooked.......

[mikesmith]

For as light as you are I cant believe they gave you that heavy of springs for a beginning trail rider,but I think the #s you want to try(or even down one more) will be right.Sorry Im not any help but I weigh about 40lbs more than you with out gear,so I cant tell you if your right on your #s or not.

[reknelb]

I just put a 5.8 kg spring on the rear and to be honest, I couldn't tell the difference. The spring that came off was an eibach 5.2 kg from what i can tell. The numbers are kinda worn, but the last 2 numbers are 5.2 sooooo I'm assuming that its a 5.2 kg.

[IridiumRed]

Well i used Racetech's online tool - which shows its recommendation for valving kit, spring rates, etc

Ironically, i even went a step LIGHTER than what they recommended.  And still can't get the sag numbers.......

Anyways, what are the true #'s for the stock fork springs?

Racetech shows them as .40 measured by them, White Brothers Catalog (a great reference) shows them as .40 as well.

But d**n, the forks hardly move when i sit on it........

Thanks for the input btw, much appreciated - i like to know when i'm on the right path, or if i'm waaaaaay out....

One thing that makes me wonder too, is that i'm getting into springs that are actually LIGHTER than what comes on most 125's today!  And supposedly they are set up for "150-160 lb test riders".  And we're talking a 500, not a 125..... but, terrain plays into that i guess (those 125's are set up for motocross)

[01KX5WOODSRIDER]

I'm 5'10" about 157lbs and I have .38kg fork springs and 5.0
shock spring. I run the clickers almost full soft off road and its
pretty plush compared to my KX-250.