How to use custom shaft clamps for inner air cans

Clamping Inner Air Cans (Air Shocks)

After removing the outer air can from an air shock (usually retained by a circlip accessible from the outside), you are left with the inner air can: a thin-walled cylinder that the air piston slides inside. On each end, a negative seal head and an eyelet are threaded directly onto the inner air can. Servicing these parts requires clamping the inner air can correctly.

What Happens If You Ovalize It?
  • The air piston will bind or drag, causing sticky behavior.
  • Air leaks will develop around the seals. These are not fixed by replacing seals alone and the inner air can will wear out.
  • Correcting a 0.1–0.2 mm deformation is difficult and replacement is often required.
    • If you bent it and need help, contact us.
    • Measure the outer diameter and find the two high spots.
    • Clamp lightly at those points.
    • Measure again.
    • Repeat until round.
  • Some shocks (e.g. Float X2) allow you to replace the inner air can , but prevention is far easier.

⚠️ This is one of the easiest parts to destroy. Take the time to do it right.

Strap Wrench?

Strap wrenches apply force in a narrow band. If you use one, position it as close as possible to the threaded area to avoid twisting or deforming the can.

For Float X2 and similar designs, use the dedicated shaft clamps included in the kit. They match the inner air can profile and prevent damage.

If the inner air can has reinforced outer ribs and you insist on using a strap wrench, strap near the threads and on a rib whenever possible.

Why Clamping Must Be Done Right

The inner air can wall is extremely thin and its inside surface is the air piston’s sliding surface. Any ovalization creates friction zones that degrade performance or cause damage.

⚠️ Always clamp vertically. Never clamp an inner air can horizontally, even slightly. Side loading will deform it.

Ensure the vise jaws span the full width of the clamp. Partial contact crushes the tube instead of holding it.

Clamping Best Practices
  • Clean thoroughly: wipe the clamp and inner air can 2–3 times with isopropyl alcohol.
  • Use paper towel: wrap the can to protect the surface and increase grip.
  • Spray isopropyl alcohol on the paper: this dramatically increases friction and requires very little clamp force.
  • Increase torque gradually: slipping means contamination is still present.
  • Do not overtighten: apply only enough force to prevent rotation.
  • Even machined clamps require clean surfaces: plastic clamps will not scratch.

Most air shocks follow this process: remove the outer air can, clamp the inner air can, then unthread the negative seal head and eyelet. Some designs (e.g. Cane Creek DB Inline) differ, but this guide covers the majority of air shock layouts.

Thanks for reading, I’ve personally done all of these myself.

⚠️ Disclaimer:

These are guidelines only. Improper clamping can damage parts. By following these steps, you accept our Terms of Service.

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