KX forks

[1989kawasaki]

What is involved in revalving? Is this something I can do myself? How do I know what it needs? I have never actually bothered changing anything, just change the oil and bleed the air. Of course I have never had a bike that I thought was worth setting up properly....

you should just send the forks away to a suspension shop cause revalving with all the shim stacks sounds too complicated to me.

[Polar-Bus]

What is involved in revalving? Is this something I can do myself? How do I know what it needs? I have never actually bothered changing anything, just change the oil and bleed the air. Of course I have never had a bike that I thought was worth setting up properly....

You really need to justify spending your hard earned money. I'm willing to bet the stock OEM '89 forks after a fluid change and possibly a set of springs to match your weight will suffice for the intended use of a casual weekend KX500. You go spending hundreds of dollars on a upgraded front end (a revalve at minimum is going to cost you $300) . You need to honestly ask yourself am I going to truly feel a positive difference ? If you were competitively  racing  your 500 now the money spent becomes more justifiable. In my 30 years of being around young dirt bikers the #1 mistake I observe is people that spend huge money  on bling and performance when they are only novice weekend riders... (I am NOT implying you are a novice weekend rider, i'm simply throwing out some opinioniated observations ). Just think before you spend...

[jkindt]

Totally agree. I wouldn't know the difference. I am not a racer, never been, never will be. I wasn't even looking for such a big bike until this deal came along. I do want to clean it up and set it up for me, but it won't be my main bike at this point. I am still looking for a deal on a KX250 that would be my main ride. This would be my 'I got a bigger bike than you' bike to pull out now and then to show off on.

[1989kawasaki]

What is involved in revalving? Is this something I can do myself? How do I know what it needs? I have never actually bothered changing anything, just change the oil and bleed the air. Of course I have never had a bike that I thought was worth setting up properly....

You really need to justify spending your hard earned money. I'm willing to bet the stock OEM '89 forks after a fluid change and possibly a set of springs to match your weight will suffice for the intended use of a casual weekend KX500. You go spending hundreds of dollars on a upgraded front end (a revalve at minimum is going to cost you $300) . You need to honestly ask yourself am I going to truly feel a positive difference ? If you were competitively  racing  your 500 now the money spent becomes more justifiable. In my 30 years of being around young dirt bikers the #1 mistake I observe is people that spend huge money  on bling and performance when they are only novice weekend riders... (I am NOT implying you are a novice weekend rider, i'm simply throwing out some opinioniated observations ). Just think before you spend...

thats true.

[jkindt]

So I have spent some time comparing parts diagrams between the KX500 and KX125 between the various late '80s and early '90s bikes. It appears I may not be out of luck with these forks after all. I thought I was getting 91-93 KX500 forks, instead I got 91-93 KX125 forks. I will have to respring them anyways, so that's not a big deal. I thought I could just bolt the forks on and use my old brakes and front wheel. It now seems that even if it had been the KX500 forks, I still need the newer brakes because they bolt up to the fork differently than the '89 conventional forks. The only thing I can see different is that I will end up with solid handlebar mounts instead of rubber mounted ones. I have the bike down to just a frame with forks, so I will pull the forks and see if the USD forks fit my frame and if my wheel bolts up. lt will be easier to get a new brake caliper than another set of forks. AND I can brag about genuine Pro Circuit forks on my bike!!! 

[jonny500]

if you can source a 91-93 kx 250 top yoke you can have the rubber mounted handle bars

[The Flyin Hawaiian]

If these forks did indeed come from Shieks bike you may not have to respring them. Usually MXrs put stiffer springs in them. Rebuild them and try them as is then decide if the springs are needed.

[jkindt]

Well...the forks definately fit. They are a direct bolt on to the frame. I think I can live with the solid handlebar mount if I have to, I got some decent 909 handlebars that are 7/8" already. The only problems I have found so far is mounting up the front tire.

1) The axle is too small on the front wheel to fit the newer fork. Can I just change the axle, or do I need to change more parts in the hub?

2) The brake caliper doesn't fit. I will just find one that matches up to the forks.

[1989kawasaki]

youll need the front wheel and brake setup from the kind of bike the forks came from

[sandblaster]

You'll need a front brake caliper from a 90-93 kx125 kx250 kx500, 91-94 kdx250.
On your front axle it will depend on your hub.
The hub will be stamped F-1212 or F-1249, possibly something else.
Or, measure your bearing diameter and tell me if it is 17mm or 20mm.

[jkindt]

The hub is stamped F-1212....tell me some good news....can I use it? 

I was hoping to get away with using the caliper and just changing the mounts, but not sure that will work...and as far as the brake disc, it is toast anyways, almost paper thin and ready to fall apart, I will just order one to match the new front end. 

[sandblaster]

Hello.
You will need a 17mm axle that FITS 90-92 KX125 KX250, 90-93 KX500 part number 41068-1310.
That should set you up.
I have a bunch of this info recorded here:
http://oem-cycle.com/KAWASAKIKX500BIKEID.aspx
The axle should look like this.

[jkindt]

Perfect! I think I should be able to find that, at least I can still use the wheel I have. Those are expensive to ship. May as well throw in new bearings and seals while I am at it since I am going this far. Thanks for all your help. 

[jkindt]

If I were to refresh my forks, would I just put in new seals and oil? Or is there internal parts that wear out and need attention? These blue forks have no play in them that I can feel, so the bushings seem fine, just one side has a slight leak.

[Polar-Bus]

If I were to refresh my forks, would I just put in new seals and oil? Or is there internal parts that wear out and need attention? These blue forks have no play in them that I can feel, so the bushings seem fine, just one side has a slight leak.

Unless your seals are blown and leaking all's I would do is flush the fluid. MX bikes usually don't have a problem with worn bushings. KX fork seals are however prone to leakage.