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Cartridge Bleeding

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I'm doing mainenance on my forks which are twin chamber Kayabas from an '05 yzf250. I'm having trouble getting the inner cartridges bled properly since the rod does not fully return after being compressed.

I'm doing the followingto fill/bleed them....

1- Vertical in vice, fill to 130mm from top, move rod up/down ~ 1in 30 times.Wait 10 min.

2- Insert cartridge. Tighten. move rod up/down ~ 1 in 30 times. Wait 10 min.

3- Put near horizontal in ice ~15 deg with holes in cartridge body at 6 & 12 o'clock. move rod up/down ~ 2in 30 times.

4- Very slowly push rod in fully. - Air escapes out of top hole about 1/2 way through stroke, excess oil comes out bottom of hole.

5- Check by pushing rod in fully. Action should be smooth and rod should fully extend.

I have the problem on step 5 where the rod only comes back about 3/4 of the way. I've tried different variations on stroking the rod up/down slowly, vertically,horizontally etc. Still get same result.:lol:

Is there another better way to bleed the forks?

Is it really necessary for the rod to come backon its own? (I would think it is)

(I should also mention that I forgot to backout the compression clicker during this, could this be a contributor or the culprit)

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These particular forks were difficult to bleed correctly without a bit of knowledge. I will provide several links for you to read, all very interesting stuff and you will see the benefits of fitting some 7-8mm spacers to the ICS springs, and also drilling a small hole in the piston, the plastic piece that moves up and down.

Once you have fitted the spacers and drilled the holes as the links describe, fill the cartridge and when you first bleed without the base valve assembly fitted, remember to have it vertical in the vice and only bleed 1", up slowly, down fast, up slowly, down fast 30x. Your opening the valve stack on the rebound piston to release the trapped air.

Top up cartridge to about 100mm and when you insert the base valve assembley hold the cartridge on an angle to try and release as much air as possible as you insert the assembly.

Then bleed again in the vice, up slowly 2", down fast, up slowly, down fast, 30x.

Now hold cartridge at about a 15 degree angle with your finger over the bottom hole and depress fully. You should hear a farting sound as the last of the air is released.

You do want the rod to extend fully when you are finished.

There is alot of interesting reading in the links provided. I hope these are of help for you and these forks. I set up a friends forks with info from these links and he was very happy with the results.

http://www.thumpertalk.com/forum/showthread.php?t=340472&parentpage=2&highlight=YZ250F

http://www.thumpertalk.com/forum/showthread.php?t=306517&parentpage=3&highlight=YZ250F

http://www.dirtrider.net/forums3/showthread.php?t=108304

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Yeah but only for a spring change. Most of the MX'rs over here know better where to spend their money, on pipes and bling rather than giving the suspension even a service during its life time, or they expect everything for free cause they are going to be the next Ben Townley.

Most my work comes from the off road bikes and the older more sensible guys with the money and no time. And I haven't seen many 07 SX's being used off road yet.

Had some apart have you?

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Changed oil in a set of SXS forks today and not entirely convinced I bled the chamber correctly. Would love to get my hands on a copy of the manual. They would fully extend but I don't understand how you bleed off the excess oil from the bladder area? It has the pop-off on the side but that seems to loose too much oil when pressed? Guess the rider will let us know? I called Jeremy and thought I had it figured out with his help but just not certain. Guess I should have called back...I didn't think about the potential problem until I was back home...I may call Jer again tomorrow to verify the procedure. :lol:

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Well keep us updated cause the time will come.

If I start to actually earn any money soon I'm planning on getting myself one of these bikes.

Just cant seem to part with any of my others.

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Would love to get my hands on a copy of the manual.

There's a repair manual CD from KTM - item # 3.206.031 - which should cost about $15, with all rapair manuals from 99 to 06.

it includes the 123 pages SXS fork repair manual with all specs, pictures etc

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Thanks, that is exactly what I needed. Much prefer to find the part # myself as some parts guys seem to struggle with the specialty items.

:confused::lol:

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I just ordered some aluminum bar to make the ICS spacers from.

If anyone is interested I'll make them some while I'm at it. They will be done in early Feb as I will be out of town till end of Jan.

PM me if interested, cost will be $10 + 2.50 for shipping.

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