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Polishing inner Cartridge rod/Reducing static friction


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Who on here polishes their inner cartridge rod on the inside or out?

Also, what other areas on the fork and shock are eligible?

Polishing the main springs is on my list. Any thoughts out there?

Jw

Edited by jwaseman
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Who on here polishes their inner cartridge rod on the inside or out?

Also, what other areas on the fork and shock are eligible?

Polishing the main springs is on my list. Any thoughts out there?

Jw

If the chrome on the fork tubes or shock shaft is free and clean, we leave it alone. Usually the only time we need to polish these is when they come in damaged, often from someone trying to polish them. Getting chrome super smooth and polished is complicated and very time consuming.

That said, we do this weird little thing where we heat the shock shaft and fork tubes to about 220F to 240F then quench them in a oil plus PTFE based fluid. This makes the chrome very smooth and super slick. Neat little trick.

For steel rods in the open bath forks, polishing them can have a great return. The aluminum rods on an open bath should be left alone as they have a somewhat fragile coating on them (comes off looking like a white powder).

On the hard anodized rods used in the closed cartridge forks (KYB and SHOWA only) we often polish these if they have that sticky and hard build-up on them. This makes a big difference. Big problem for a lot of late model CRs and YZs. Seems to be a problem with the fluid.

When we clean the inside of the upper tubes, and the shock bodies, we have a cleaning method to make sure we break down any light residue, but you have to be VERY careful about not going too far as you can start to cut into the coating. I usually advise not doing this as it's very tricky and often not worth the risk.

Lastly, we do pay a lot of attention to bushing fit as this can cause a lot of static friction if it's not just right. The 05 YZs are the worse and often those upper tubes have to be machined.

And of course, we cut or machine the bands on the 50mm shocks. That can make a big difference. I wonder now if the reason why they are going to an x-ring design on the 2010 RMZs is to help resolve this issue.

And yes, we polish the outer edge of the fork springs. This is actually a cool trick because it keeps the oil cleaner, longer...and reduces static friction.

Oh...one more thing. Sometimes we also polish the inside of the lower fork tube. Takes a very long extension and some special pads, but it can be done and worth the effort.

It's amazing how much cleaner and smoother everything can be made with a little work, all of which I would recommend before someone spends too much on some high end coating.

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On revalves I always polish springs AND cartridge rods.

Does it make a difference?? Sure does in my head:bonk:

Really though it doesn't nasty the oil up as quick:ride:

Thanks for the reply ds, Do you remove the anodized coating completely from the rod?

If the chrome on the fork tubes or shock shaft is free and clean, we leave it alone. Usually the only time we need to polish these is when they come in damaged, often from someone trying to polish them. Getting chrome super smooth and polished is complicated and very time consuming.

That said, we do this weird little thing where we heat the shock shaft and fork tubes to about 220F to 240F then quench them in a oil plus PTFE based fluid. This makes the chrome very smooth and super slick. Neat little trick.

I would love to hear more about this process, If the process details needs to be kept under wraps, I understand.

For steel rods in the open bath forks, polishing them can have a great return. The aluminum rods on an open bath should be left alone as they have a somewhat fragile coating on them (comes off looking like a white powder).

Do you polish on the inside as well?

On the hard anodized rods used in the closed cartridge forks (KYB and SHOWA only) we often polish these if they have that sticky and hard build-up on them. This makes a big difference. Big problem for a lot of late model CRs and YZs. Seems to be a problem with the fluid.

While removing the build up do remove the anodized coating? HOw about on the inside of the rod?

When we clean the inside of the upper tubes, and the shock bodies, we have a cleaning method to make sure we break down any light residue, but you have to be VERY careful about not going too far as you can start to cut into the coating. I usually advise not doing this as it's very tricky and often not worth the risk.

Lastly, we do pay a lot of attention to bushing fit as this can cause a lot of static friction if it's not just right. The 05 YZs are the worse and often those upper tubes have to be machined.

And of course, we cut or machine the bands on the 50mm shocks. That can make a big difference. I wonder now if the reason why they are going to an x-ring design on the 2010 RMZs is to help resolve this issue.

And yes, we polish the outer edge of the fork springs. This is actually a cool trick because it keeps the oil cleaner, longer...and reduces static friction.

Oh...one more thing. Sometimes we also polish the inside of the lower fork tube. Takes a very long extension and some special pads, but it can be done and worth the effort.

What type or kind of extension are you using? How are you attaching the pads?

It's amazing how much cleaner and smoother everything can be made with a little work, all of which I would recommend before someone spends too much on some high end coating.

Thank you Dave for being so open about your processes. 😏

I would like to hear more from other folks as well if they would like to share!😏

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I'm always polishing the inner tubes (fork) and the piston rod (shock).

i usually don't touch the cartridge rod if it's coated to not take away the coating. There are some (older? ) coatings which feel like sandpaper. Those i'm polishing very carefully to get rid of the rough surface, trying to not harm the coating.

All non-coated rods get a polishing if i think it'd make sense.

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Yes, especially if its new! How about you ccie, any polishing going on?

No, but I think in certain areas as you and others have mentioned makes perfect sense like oil contamination in the outer tube. Then the IC I wonder if doing this could alter mv piston band resistance or possibly do the opposite for reduced stiction resulting in less oil breakdown 😏

Could this also affect dampening?

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I use Scotch Brite ultra fine gray for rods and it def doesn't take any of the coating off. Basically I'm just polishing the rods to get the tacky gunk off of it that some oils leave behind.

Wish I had a lathe though as I tore a set of 09' WP's down last night for revalve and seal change and the water spots on the chrome tubes wouldn't come off even with the gray scotch brite:banghead:

Now that's some nasty water:bonk:

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