KYB fork rebuild/set up for my 89 kdx

Questions and comments about converting to beefier forks..
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Cskarke
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KYB fork rebuild/set up for my 89 kdx

Post by Cskarke »

Mega score!! Just picked up a 1997 kx250 parts bike and a 93 kdx 200 part bike for $140! Kx doesn't have much on it except the entire front end which is exactly what I was after! Now I need to completely rebuild those forks before I get my 89 kdx ready for the conversion and of course I want to set them up right from the beginning. Problem is, is that Im a complete suspension newb. Ive rebuilt every single component on dirtbikes except shocks and forks so I know I can learn how but I know I need some help as well.

The biggest thing I want to learn is how to set them up properly for my riding style. The last thing I want to do is to rebuild them to factory specs and then get beat to death on the trails (I have a yz for that and it does a very good job at kicking my butt). So any help is appreciated, even video suggestions or pasts post on this topic will help if you dont feel like writing novels on stuff thats already been posted before.

If you do have some good advice to give for my specific set up, then here is what I know.
*1989 Kdx 200 about to be converted to accept the KYB forks from a 97 kx250
*Im 6'1" and weigh 195lbs with gear on. (dad bod coming in hot so that has a high likely hood of increasing the next few years)
*The West Texas trails that I normally ride vary ALOT ( Rocks, Roots, Ruts, and Sand usually all in the same day of riding... Rough hard packed dirt trails that have been ate up by SXS & 4x4's are probably the most common riding for me)
*I also plan to race a few enduros here in West Texas, did my first 2 races this last year on the My YZ250 and even with the clickers all the way soft, I got the snot knocked out of me on those rough rocky courses..
* Another question I have, Once these forks are set up for trail properly, will I Have enough room in the clickers to crank them up and play around on some pretty decent jumps? Id like to sell the YZ so I can focus all my spare time and money on the KDX and really build it into what Id like (Check out "badhusker" on Instagram and the e series that he built for the teampryme bike build contest, cleanest e series Ive seen) Might be a bad idea to jump the kdx but i figured id throw it out there to see what you guys have to say.

So this is what Id like to know or what I can think of off the top of my head
*Revalving? Need to? If so, what do I need?
Type/brand/weight Fork oil?
Spring rate? Need to change from factory? I dont want to unless it just makes a big difference in the final result!
Fork height set in the triples?
Clicker settings if yall have a suggested starting point.
And last thing, where should I look for good instruction on how to take apart/rebuild these specific KYB's? I'm sure I can just search it on Youtube but if yall know of any specific videos or set of instructions that are out there, then Id love to see them!
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KDXGarage
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Re: KYB fork rebuild/set up for my 89 kdx

Post by KDXGarage »

Congratulations on the pre-COVID pricing!

http://kdxrider.net/Kayaba.htm

If the fork springs are stock, then they are 0.40, may be close enough for what it sounds like you are doing.

The stem will need to be knurled, as the stock stem is not as wide as what is currently in the 1997 KX250

5 weight oil, Kawasaki sells Kayaba rebranded as Kawasaki, otherwise Silkolene, etc.

Yes, it will need a revalve. It has a midvalve in stock form. The base valve and midvalve work together on compression. I assume it just has a check valve on rebound side of rod.

It won't be like jumping a YZ, especially after turning the MX forks into woods forks.
Thank you for participating on kdxrider.net. :bravo:
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Cskarke
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Re: KYB fork rebuild/set up for my 89 kdx

Post by Cskarke »

KDXGarage wrote: 02:19 pm May 19 2021 It won't be like jumping a YZ, especially after turning the MX forks into woods forks.

Yeah I don't plan on sending it quite as hard as the yz but as long as the kybs can handle a jump a little better than the stock conventionals than I'll be happy. Not my main purpose or I'd just leave them stock obviously! Just would be nice if the clickers did more on the kybs than they do on the conventionals.

And thank for all that other info! Iooks like I've got my work cut out for me!
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Re: KYB fork rebuild/set up for my 89 kdx

Post by KDXGarage »

The clickers will indeed provide a better range of adjustment.
Thank you for participating on kdxrider.net. :bravo:
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Re: KYB fork rebuild/set up for my 89 kdx

Post by Slick_Nick »

In my opinion, there’s no such thing as a “do it all” fork. If you want it to be able to soak up even medium sized jumps, you’ll need them stiff enough that the small stuff will be uncomfortable.

I revalved mine and after a couple iterations they are the smoothest forks I’ve ever ridden off road. I have bottoming resistance for a 5’ drop, but they are super plush for all the small stuff, and I have a separate bike if I want to do MX, the KDX really isn’t the right bike for it.
'00 KDX 220R
Cskarke
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Re: KYB fork rebuild/set up for my 89 kdx

Post by Cskarke »

Slick_Nick wrote: 07:50 pm May 19 2021 In my opinion, there’s no such thing as a “do it all” fork. If you want it to be able to soak up even medium sized jumps, you’ll need them stiff enough that the small stuff will be uncomfortable.

I revalved mine and after a couple iterations they are the smoothest forks I’ve ever ridden off road. I have bottoming resistance for a 5’ drop, but they are super plush for all the small stuff, and I have a separate bike if I want to do MX, the KDX really isn’t the right bike for it.
Might be no such thing as a "do all" but there definitely needs to be! Would save space in the garage, lol.
What all did you do to get it How you like? And what forks you got?
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Re: KYB fork rebuild/set up for my 89 kdx

Post by SS109 »

The Marzocchi PFP 48mm forks come close to a "do it all" set of forks. The externally adjustable cartridge pressure makes it great for hitting the MX track and then hike-a-bike technical terrain a few hours later. Sorry, I'm a Zoke PFP fan boy! :mrgreen:

That said, I'm very happy with my 47mm Showas on the KDX. A few clicks either way and I can safely ride (I'm not catching any serious air or jumping any do or die jumps) anything I care to.
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Re: KYB fork rebuild/set up for my 89 kdx

Post by Slick_Nick »

Cskarke wrote: 10:34 pm May 19 2021
Slick_Nick wrote: 07:50 pm May 19 2021 In my opinion, there’s no such thing as a “do it all” fork. If you want it to be able to soak up even medium sized jumps, you’ll need them stiff enough that the small stuff will be uncomfortable.

I revalved mine and after a couple iterations they are the smoothest forks I’ve ever ridden off road. I have bottoming resistance for a 5’ drop, but they are super plush for all the small stuff, and I have a separate bike if I want to do MX, the KDX really isn’t the right bike for it.
Might be no such thing as a "do all" but there definitely needs to be! Would save space in the garage, lol.
What all did you do to get it How you like? And what forks you got?
My forks are off a '95 KX125. First year of the midvalve, but no stupid bladders. After i revalved them, they are amazingly plush offroad. When I first tested them out I ran straight into a street curb outside my house going pretty quick and didn't even feel it.
'00 KDX 220R
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