One easy way to custom tune your fork’s air-spring performance is to add or remove Bottomless Tokens, which change the fork's air-spring curve.
Depending on what type of rider you are, and your preference for suspension, will affect whether you want more or less tokens than the next rider.
A more aggressive rider will want to add Bottomless Tokens to prevent bottom-out, but less aggressive riders may want to remove Bottomless Tokens for a more linear feel and to benefit from more of the fork's travel.
Below are six steps to adjusting your fork's air-spring curve using Bottomless Tokens.
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What is a Bottomless Token?

This is RockShox’s name for its air fork volume spacers (air shock spacers are known as Bottomless Rings).
Grey tokens fit in Revelation, Pike, Yari, Lyrik and BoXXer forks, while red ones are slightly wider and only fit in the Pike.
You'll need:
- Workstand
- Shock pump
- Slim ball-ended Allen key or similar
- 24mm socket or cassette lockring tool
- Bottomless Tokens
- 8mm Allen key
- Grease
1. Clean your bike

Ensure your bike is clean, to prevent dirt falling into the fork. It’s also best to hang it in a workstand.
Remove the air-valve dust cap from the non-driveside of the fork (turning it anticlockwise) and put it somewhere safe.
2. Measure the spring pressure

Attach a shock pump to the valve and note down the spring pressure.
Remove the pump and press a slim ball-ended Allen key — or similar — into the valve to release all the air from the fork.
3. Remove the air cap

Use a 24mm socket (or cassette lockring tool, on 2018 forks) to unscrew the air cap, ensuring that it’s pressed firmly onto the nut (anticlockwise).
Remove the air cap and you should see any pre-fitted Bottomless Tokens screwed into the bottom of it.
4a. Add tokens

For a more progressive spring rate, add one or more tokens, by screwing them into the air cap (clockwise).
Use an 8mm Allen key and 24mm socket to tighten them until gently snug (1.1-2.3Nm).
Do not exceed the maximum number of tokens for your fork (Varies by fork model, travel and wheel size. Check your owner’s manual or SRAM for details).
4b. Or, remove tokens

If you want a more linear feel, remove one or more tokens, by unscrewing them from the air cap.
Use an 8mm Allen key and 24mm socket, turning them anticlockwise. Ensure that the remaining tokens are tightened to 1.1-2.3Nm.
5. Replace the air cap

Grease the air cap O-ring and reinstall the air cap in the fork, turning the 24mm socket by hand to reduce the risk of cross-threading (clockwise).
Tighten the air cap to 24Nm, while applying downward pressure on the socket to avoid rounding the nut.
6. Re-inflate the spring

Reattach the shock pump to the valve and reinflate the spring to your desired pressure.
Push down on the fork a few times to balance the pressure in the positive and negative air chambers. Re-check the air pressure and compensate if necessary.