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225 lbs riders (no gear), what are you using for spring rates?

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Bike: '07 kx450f

Type of riding: Motocross

Riding skill: Mid pack B rider

Terrain: hard packed

Suspension valving: Stock (don't have the money for suspension work yet, but want to start out with correct spring rates)

I bought a 5.7 kg/mm for the rear according to what the race-tech spring calculators suggest for my weight, but as I search & read what other riders are using in these forums it seems they're using higher rates. What are you guys using?

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I'm in the same rider category as you, but I had my suspension revalved. Anyway, I'm runing 5.8 in the rear.

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I bought a 5.7 kg/mm for the rear according to what the race-tech spring calculators suggest for my weight
Did you install it, set your rider sag to your favorite figure and check your rear static sag is in the 25 to 35mm range?

Too little on the static and your spring is too soft. I'm assuming fork springs are in the ball park.

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I was the same, had a revalve, but was running a .049 and 6.0, I would have liked a 5.9, but they didnt have a kayaba in stock at the time.

As far as the shock spring, just need to check your sag and the bikes free sag. 100mm / 25mm.

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[i was the same, had a revalve, but was running a .049 and 6.0, I would have liked a 5.9/QUOTE]

I've asked several suspension shops & most suggest a .49 for the front so that's what I'm getting. I just wonder if I'm too light at the rear with a 5.7.

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I've asked several suspension shops & most suggest a .49 for the front so that's what I'm getting. I just wonder if I'm too light at the rear with a 5.7.
Why not just install it, and set and measure your rider sag (eg. set it to 102mm with gear on) and then measure static sag and ensure it's not less than 25mm?

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[/Why not just install it, and set and measure your rider sag (eg. set it to 102mm with gear on) and then measure static sag and ensure it's not less than 25mm? QUOTE]

Yes..., you're right. Is the second time I've been told:bonk:, point taken. Is not my fault, I was born this way, but since I'm already in this world, I have deal with it now. Thanks.

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I really feel that a .049 mated with a 5.7 rear spring will feel unbalanced, too light in the ass or too springy in the front, depending on weight.

Instal and check your sag, if its good, shock is done, but test your forks well, as I really think if the 5.7 works, your forks will ride too high and be harsh.

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Call Dave at SmartPerformance. Also, see iff someone is ditching theor 2010 springs because they went up by one unit front and rear and that might be the ticket. But def call dave and he will sell you his midvalve kit for the forks. Cheap and easy to install. You will love it. Love it!!

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Call Dave at SmartPerformance.

I did. He suggested a .49 for the front & a 5.9 for the rear. He also mentioned that with valving I could get away with the 5.7 on the rear. I also called DSP Racing & they said .50 for the front & 5.9 for the rear.

Don't install it! return it and get what you need! If you scratch it or chip it they won't take an return on the spring!

Too late, he 5.7 has been installed for about 3 months now (although for work reasons I've barely rode the bike). If I need a stiffer spring, I guess I'll try to sell it.

Bottom line: I'm going to do what Numroe suggested; set the sag at 102mm (with riding gear on) & then measure the static sag. That will tell me where I'm at with the 5.7 on the rear & also will give me an idea what to get for the front, but since I work away from home during the week I'll have to wait until the weekend to do this.

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