Fork Springs for 1992 KDX200

Questions and comments about converting to beefier forks..
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SCARYMOOSE69
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Fork Springs for 1992 KDX200

Post by SCARYMOOSE69 »

Hey Guys,

Just got a 1992 KDX200 and took it for the first ride, while i love plush front forks, they were way too undersprung for my 170 lb ass.

Im wondering do all fork springs work with the conventional style forks regardless of model year? Like will springs from the 1995 on KDX's work on the 1989-1992 forks?

Also looking at race techs, and going with .40 kg/mm, anyone know what model # is the ticket on that?

One more question too, my old honda XL's have progressive springs, are the regular stiffer springs good enough or do progressives make a difference on the KDX?

Thanks!
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Re: Fork Springs for 1992 KDX200

Post by KDXGarage »

Are you 170 with all your riding gear, spare tools, spare parts, water backpack, etc.?

EDIT ADD ON:

The stock springs are only 0.30! The 1995+ springs are only 0.35. Neither is stiff enough.

Use linear rate instead of progressive rate.

A current model YZ250X off-road bike comes with 0.44 rate. It is about 12.5 pounds lighter (roughly) than a KDX. Keep that in mind when spring shopping. Basically, early 90's spring rate thinking is much different than now.
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SCARYMOOSE69
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Re: Fork Springs for 1992 KDX200

Post by SCARYMOOSE69 »

170 in my birthday suit haha, good thing to factor in, i ususually prefer a lighter suspension though.

Wow didnt know they were that light!

But to the main question, will the 1995 on springs work length and OD wise in the 1989-1992 forks?
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Re: Fork Springs for 1992 KDX200

Post by SS109 »

Hmm, not sure on if the springs will swap.

Anyway, for comparison, my buddy weighs 170 without gear and runs .40 springs up front and I run the same on my KDX yet only weigh 140 without gear.
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Re: Fork Springs for 1992 KDX200

Post by KDXGarage »

Yes, 1995+ springs will fit. 0.35 is better than 0.30.
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Re: Fork Springs for 1992 KDX200

Post by SCARYMOOSE69 »

Ok sweet, im probably gonna go with racetechs or fredette springs, but i wasnt sure if they were specifically for the later models.

Ive seen the XR400 swap is popular too but my ebay searches are looking like the aftermarkets are the way to go.

I see the race tech FRSP 3750K with the 3 extra little springs is probably the cheapest option, with all the springs installed itll give me .40 apparenttly.

Looks a little suspect stacking springs, fredette looks better but more expensive.

What aftermarket springs are you all running?
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Re: Fork Springs for 1992 KDX200

Post by SCARYMOOSE69 »

Quick question too, im scarred from trying to ride singletrack with my old CR motocrossers, the shocks were rock hard and unforgiving.

I checked OEM spring rates on those, and theyre around .38-.4 between what model i had and year (85 cr250, 97 cr125) Im assuming this is due to the valving, and not necessarily the springs only.

Enduro valving with heavier springs on the KDX200 wont be as hard as MX valving on those CR's, right?
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Re: Fork Springs for 1992 KDX200

Post by SS109 »

SCARYMOOSE69 wrote: 11:39 pm Feb 28 2022 Quick question too, im scarred from trying to ride singletrack with my old CR motocrossers, the shocks were rock hard and unforgiving.

I checked OEM spring rates on those, and theyre around .38-.4 between what model i had and year (85 cr250, 97 cr125) Im assuming this is due to the valving, and not necessarily the springs only.

Enduro valving with heavier springs on the KDX200 wont be as hard as MX valving on those CR's, right?
Springs are just for carrying the bike's and your weight, nothing more. Valving definitely plays a huge part in how they feel, though, and the KDX's are valved a lot more compliant than any MX'ers valving. For your weight the stock rear spring is pretty much spot on, and with the stock valving, should work well for you. Just don't forget to set your sag properly!
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Re: Fork Springs for 1992 KDX200

Post by KDXGarage »

Adding a spring makes the total rate softer. I would get the 3750 kit.

Most sellers on eBay are asking very high prices for used springs. I have seen some where it is just a little more to buy new.
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