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Understanding the function of KYB forks

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Could some one give a brief desciption of how the damping circuits work on the bladder style KYB forks...mabye with a diagram?

1) I'd like to further understand mainly which side of the MV and BV is rebound and compression.

2) How the oil flows thru the fork during the compression and rebound cycles...this would be really helpful.

I am no Guru like some of you guys but I like working on my own stuff, I had some great results revalving Showa forks for trail riding but no experience with KYB's

Thanks for any help!

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KYB forks do not have a bladder.

If you've worked on Showa TC forks, the KYB TC fork is basically the same, as far as which side of the MV and BV are compression and rebound.

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i think he means the older style kyb bladder fork?

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KYB forks do not have a bladder.

CR125 00-07

KX125 00-02, 04-08

KX250 00-02, 2004

KX250F 04-05

RM250 01-02

RM-Z250 04-06

all those Kayaba forks come with a bladder + really old ones

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I know this is a crude drawing and probably not very accurate but something like this with oil flow arrows for compression and rebound would be very helpful to those of us that want to learn more about suspension.

And many would like to see the same for the current design Showa's and kyb's

KYBfork.jpg

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Dynamic_view_of_cartridge.gif

This is the old style recirculating system. Notice the oil going up through the center of the cartridge rod and squirting out the side just below the cap? The later models have the oil exit through a hole in the side of the rebound tap/stem. Keeps the pressure in the cartridge and doesn't allow it to suck air on rebound like the recirculating system did.

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Dynamic_view_of_cartridge.gif

This is the old style recirculating system. Notice the oil going up through the center of the cartridge rod and squirting out the side just below the cap? The later models have the oil exit through a hole in the side of the rebound tap/stem. Keeps the pressure in the cartridge and doesn't allow it to suck air on rebound like the recirculating system did.

That's great and easy to see how the oil flows thru the valving

Tks

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dont think the 91 came with a bladder? it started in the 2000s as far as i can remember?

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Now for the most important part pertaining to the KYB bladder fork, disabling the bladder.

Just remove the bladder itself or the external piston ring at the top of the cartridge.

Now that you have improved your bladder fork by removing that slimmy piece of crud you must run conventional OC fluid heights ranging from 80mm to 130mm from the top, forks collapsed, springs out.:D

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Dynamic_view_of_cartridge.gif

This is the old style recirculating system. Notice the oil going up through the center of the cartridge rod and squirting out the side just below the cap? The later models have the oil exit through a hole in the side of the rebound tap/stem. Keeps the pressure in the cartridge and doesn't allow it to suck air on rebound like the recirculating system did.

How the hell............how you do that? Magic?

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