01 fork seal change and valving, pic heavy.

[no1clyde]

OK today I took the 01 forks apart and changed the seals and the valving. As for the valving I am not recommending this change and do not know what it will work like. I am leaving the bladder in and am trying to make them work with it. I put a Yamaha floating compression mid valve, used the stock Kawasaki rebound valve and pulled 4 face shims out of the base valve, put Mobil1 atf in them at 100mm from the top. This is just to see what will happen, I am prepared to do this as many times as it will take to get them to where I like them. These are spare legs and my normal forks are ready to back on. First ride was hitting the curb out in frount of the house and they felt pretty good but a real test is needed.

I started by removing the base valve with a impack wrench and drain the oil.

Then the top nut.

Pull the cartridge out the top.

Then heat the seal area with a heat gun and then slide hammer them apart.

Then take the wiper, snap ring, seal washer, and 2 bushing off.

Then clean both tubes and put the new seals on with some plastic to protect the seal face.

Put on the washer and 2 bushings and start the tubes together.

Using a seal driver install the bushing and washer.

Then the seal, snap ring and wiper.

You have now changed the seal. We are now going to take the cartridge apart. Take the top nut off.

Remove the spring and then the spring guide. Now take the bottoming piston apart.

Then take the piston off by removing the split keepers.

Then slide the rod out of the cartridge, the mid valve is on the end.

A bad pic but this is the mid valve and the base valve.

The shims removed off both in order.

On the Kawasaki there is no clearance or float in the compression side of the mid valve. On the Yamaha there is float or clearance that has a spring to hold the shims against the piston on rebound. The Kawasaki has a O-rig that keeps everything up against the piston. These are the Yamaha parts I used to make float, about 1mm of float.

The modified mid and base valve ready to go in.

Put the cartridge this far back together.

Then put it in the tubes and screw in the base valve and tighten. Then I put it in a vise I have on the floor to make it easier to put in the oil. Leave the spring out for now to set the oil level.

Then the oil to 100mm from the top with the forks collapsed and no spring.

Then put on the spring.

Then tighten up the top and you are done.

These are the tools that I used.

I hope I didn't confuse you guys too much. This was harder than the motor stuff to try to make it make sense. I DONOT recomend anyone to try my revalve I just thought you guys would like to see the insides of the fork. I had to remove 3 pics but I think this will work.

Ed

[no1clyde]

Also the black stuff on the outside of the cartridge is the bladded. And for KDXGarage there is no rubber bottoming stop just a long bottoming cone for the piston. I also recorded the stock shims sizes if anyone cares I will post them.

Ed

[ebeck]

Wow been looking for pics on the process. Thanks Ed!

[MTO]

Please let us know how they work for you. I just recently removed 5 of the 10 large (24's) shims on the base valve and found that the bladder had already been disabled on my 02's but I havent tried them out yet.

[KDXGarage]

Thanks for the pictures and information!

The bladder setup looks very similar (might be the same?) as the 2000 forks I worked on.

[no1clyde]

KDXGarage I think the 00 and 01 are the same.

For those that have never done this before you need to stroke the damper rod up and down when filling with oil until all the air is out of the cartridge, this bleeding the cartridge. And on both the base and mid valves the shim stack in the mid or check plate in the base by the nut is the rebound and the stacks on the other side of the piston is the compression.

MTO if your forks have a stock mid valve compression stack they will be fairly stiff. The mid is part of the secret to make modern forks work.

Ebeck if your new sig is for me, well maybe,OK. I am my own worst enemy but if I am messing with myself I am leaving the masses alone,LOL.

Ed

[MTO]

Is the yamaha midvalve modded or direct replacement?

I will mess with the midvalve next time I have them apart, I just filled em with davej's magic snake oil ?

I don't want them to be too mushy with a disabled bladder AND the midvalve mod. I don't even have the parts to enable the bladder.

Thanks for the awesome write-up!

[shrubitup]

does that massive syringe suck all the used oil out? the last time I did this was a while ago on a 1977 XR75 back in 1982.? Open nut, compress front brake, pump forks up and down to get all oil out.

[no1clyde]

shrubitup no the massive syringe is to suck the oil out at the hight that I set the part sticking in to the oil, in this case 100mm. I get the used oil out by removing the base valve and dumping it out the bottom.

MTO let us know what you think of Daves oil. You may want to ask him what to do to your forks if you are still not happy. He seems to be one of the best with these forks. As for the Yamaha mid valve it was not moded yet but I did have to use the Kawasaki spring cup to make it fit.

Thanks all for the nice comments.

Ed

[no1clyde]

Well I just got back from riding the bike and it is hot, dry, and slick out here where I ride. The forks worked OK, they can be better though. Even with all those changes they are just a little stiff still but not bad. I may lower the oil level and change the base valve a little more. But for now I will ride it some more.

Ed

[Jeekinz]

Thanks for the update Ed.

[Borci88]

Quick question since this is a Forks thread ?

I have an '84 KX80 so it doesn't have USD forks, what do I put into the top of the forks, it's an air valve so I assume just air? A mate said nitrogen but I'm pretty sure he was just joshin me. Don't have the manual on hand at the moment unfortunately.

[don46]

Quick question since this is a Forks thread ?

I have an '84 KX80 so it doesn't have USD forks, what do I put into the top of the forks, it's an air valve so I assume just air? A mate said nitrogen but I'm pretty sure he was just joshin me. Don't have the manual on hand at the moment unfortunately.

Nothing! use the valves to remove air, if you put air in you will more than likely blow the fork seals, remember as the forks are compressed the volume inside gets smaller, so you get some natural pressure buildup that will act as a air spring.

MTO, what did you mean by enable the bladder? if they are in there they are probably enabled,

[RandoShadow]

i have a 2001 too and I am doing the same think. well, almost. I am not messing with the shims. just putting new seals on.

i should be taking pics but i forgot too :S

[Borci88]

Nothing! use the valves to remove air, if you put air in you will more than likely blow the fork seals, remember as the forks are compressed the volume inside gets smaller, so you get some natural pressure buildup that will act as a air spring.

MTO, what did you mean by enable the bladder? if they are in there they are probably enabled,

Really? Just seems extremely spongy.. Like I can stand on the bike like a trials bike, and jump up and down and the front wheel will come off the ground after 2 or 3 jumps... maybe put some more fork oil or heavier oil?

Matt.

[KDXGarage]

You may want to start a new thread, as someone might catch the title and have advice for you. Saying that this is a fork thread is a little better than cutting in on a "this is a motorcycle related thread", but...

[Borci88]

You may want to start a new thread, as someone might catch the title and have advice for you. Saying that this is a fork thread is a little better than cutting in on a "this is a motorcycle related thread", but...

No point, it's a simple question, but thanks for your concern.

[MTO]

MTO, what did you mean by enable the bladder? if they are in there they are probably enabled,

there is a spring and sealing washer just above the bladder you see in the pic. they have been removed in mine, rendering the bladder useless. the bladders are still in, but they don't work.

[KDXGarage]

Here's a late point. The end of the damper rod has the rebound valving at the bottom of the piston. The valving on the top is the midvalve (found on 1995 and newer KX forks, no KDX's ever came with a midvalve).

[zukboy789]

I surely hope you put tape on the fork tube before using the fork seal driver. Otherwise, is with scratch the fork tube causing excessive wear on the seals.