Fork internal damping cartridge stack

[budd]

I'm after one of these ...


it goes into the base of the damper cartridge in the forks, not sure what the technical term for it is, damping stack? lower cartridge valve?
either way if anyone as one pls let me know, or if you have any bent forks (Alistair?), I'm ready to rebuild the forks but can't till I get one of these.

cheers

[Shauned71]

No idea how you take these things to bits.... Is what you are after in the end of this?

[Cadbury64]

No idea how you take these things to bits.... Is what you are after in the end of this?

Screw a 30+mm long bolt a little into the thread on the end and tap that gently to push the base valve in until you find the thin wire circlip, that can be hooked out, then you can pull the base valve right out of the cartridge tube.

[budd]

yes has stated above it's in the bottom of the tube, push it in remove small cir-clip and push it out with the damper rod, it should come out fairly easily it's just a push fit with an O ring let me know how you get on

[AMCQ46]

I'm after one of these ...


it goes into the base of the damper cartridge in the forks, not sure what the technical term for it is, damping stack? lower cartridge valve?
either way if anyone as one pls let me know, or if you have any bent forks (Alistair?), I'm ready to rebuild the forks but can't till I get one of these.

cheers

I gave the ones out of my bent forks to Gabi

[Shauned71]

I have it but it don't quite look like yours...

[budd]

I have it but it don't quite look like yours...

that's strange I would have assumed they would be the same, but they are indeed slightly different, do you have a pair ?

[budd]

I'm after one of these ...


it goes into the base of the damper cartridge in the forks, not sure what the technical term for it is, damping stack? lower cartridge valve?
either way if anyone as one pls let me know, or if you have any bent forks (Alistair?), I'm ready to rebuild the forks but can't till I get one of these.

cheers

I gave the ones out of my bent forks to Gabi

he hasn't get them now

[Shauned71]

I have it but it don't quite look like yours...

that's strange I would have assumed they would be the same, but they are indeed slightly different, do you have a pair ?

I do... pm me address and i'll get it sorted. Should get them posted today

[budd]

That's great, I've pm'd you my address, let me know how much I owe you

[tony.mon]

If those don't fit I have a pair of usd 954 forks I don't need.

[budd]

Cheers Tony

[Cadbury64]

The difference between those two valve setups is that one has the fixed bleed port down the middle of the bolt and out through the visible hole below the valve body. The other set probably has either a small spacer (0.1mm x 12mm) keeping the face shim clear of the valve body which I suspect is stock for the VTR, or it may have small channels machined into the valve body sealing face.

You do need some form of a fixed bleed which bypasses the compression shims, but not too big or you will lose some of the feeling of control, a typical size is 1.3mm diameter. Another variant is what I have observed with Rogered forks where the bypass has been drilled through the wall of the cartridge tube below the sweep of the rebound piston. Or you can do what RaceTech advise which is to drill the bypass through the wall of the compression valve body, easy to do on their aluminium bodies, not easy on the sintered metal Showa part.

[budd]

The difference between those two valve setups is that one has the fixed bleed port down the middle of the bolt and out through the visible hole below the valve body. The other set probably has either a small spacer (0.1mm x 12mm) keeping the face shim clear of the valve body which I suspect is stock for the VTR, or it may have small channels machined into the valve body sealing face.

You do need some form of a fixed bleed which bypasses the compression shims, but not too big or you will lose some of the feeling of control, a typical size is 1.3mm diameter. Another variant is what I have observed with Rogered forks where the bypass has been drilled through the wall of the cartridge tube below the sweep of the rebound piston. Or you can do what RaceTech advise which is to drill the bypass through the wall of the compression valve body, easy to do on their aluminium bodies, not easy on the sintered metal Showa part.

thanks for the info, I'd assumed they'd all be the same, anyway sorted now, thanks to Shauned71 a pair are winging there way to me, I'll be drilling the bypass in the cartridge tube as per Rogered forks, I've done this before and it seems to work well.