How to tune your suspension perfectly

Undoubtedly, your suspension is the most complex part of your bike, and therefore the hardest to get right.  For those wanting to take their riding to the next level, you need to be willing to adjust more than the air pressure or the compression.  Taking apart your fork or shock may seem daunting at first, but in reality it requires very little mechanical know-how.

I won’t focus on telling you how to add or remove parts from your suspension in this article, as there are plenty of far more qualified people than me who have made YouTube videos on this topic, some of which I’ll link to in this article.  I am, however, going to tell you when and why you should adjust the internals of the bouncy parts of your bike.

30 second guide 

  • If you bottom out a lot, but your sag is right, add spacers.
  • Keep the same air pressure before and after you install tokens.
  • The more aggressively you ride, the more spacers you’ll need.


You can adjust almost everything on your fork, from the oil to the internals and everything in between, but the most common adjustment, and the most useful, is changing the the volume in the air canister of the fork. This is achieved by adding volume spacers, or bottomless tokens for a Rockshox fork. These are essentially expensive pieces of plastic that alter how your fork moves through its travel, most noticeably in the last third of your fork’s stroke. When adjusting the tokens in your suspension, you’ll often hear riders talking about the progression of their fork, this refers to how the resistance of the fork to compression. If there is no change in resistance throughout the stroke, i.e, you’ll use travel at the same rate in the first half as you do in the second half, the suspension is said to be linear. If the level of resistance increases with the amount of travel used, meaning that the fork gets harder to compress the farther through its travel you are, the suspension is said to be progressive.  Volume reducers are specific to your fork, so be sure to check that you are purchasing the correct spacers for your suspension.   

Screen Shot 2017-04-19 at 1.11.23 pm.png

This graph shows adding tokens to your suspension increases the amount of force required to use the same amount of travel.

Volume reducers are a great tool to know about, and if you decide you need them, it’s an incredibly simple thing to change.  What you do need to know is that they customise, not improve, the performance of your fork.  You should only add volume spacers if you need them.  The general rule of thumb is that if your sag is right, but you find that you’re bottoming out too much, then you’ll need to add volume spacers.  For Fox, start with one additional blue token, and for Rockshox, if you currently have no tokens installed, start with two, and tweak from there.  If you have the benefit of a nearby bike park, or a mate willing to shuttle you, you could try what’s known as bracket testing.  This means taking your suspension to its extremes, i.e, try no tokens, and then try the maximum for your fork, and gradually narrow down on the perfect number for your bike.  This is a great method, but it’s very labour intensive, and whilst it may find a better performing fork in the end, it will take much longer.


The Rockshox bottomless tokens

Essentially, the more aggressive a rider you are, the more tokens you’ll need.  Tokens are most useful in big hits, ramping the resistance of your suspension so you don’t bottom out, but they also prevent the fork from diving in big G (gravity) outs, giving you a more stable platform for big berms.  Additional tokens will also give you more of a ‘pop’ off lips, helping you out in the air.

If you want to learn how to install volume spacers, check out this awesome video by GMBN for a tutorial on a Fox fork.

Here’s a useful video by MBR for a Rockshox fork.


Shock volume reducers operate off the same pneumatic principles as those in the fork.  These are slightly more labour intensive to install, but still require no great level of skill.  Fox volume reducers manifest in a similar fashion to those in the fork, but RockShox are known as bottomless rings, and are essentially rubber bands that wrap around the internal air canister.  Using the same principle of when to adjust the volume in your fork, you can apply to your shock, and finding the right number of bands will again be a process of trial and error.

For the suspension geeks out there, adding volume spacers only affects your positive pressure, not your negative pressure, meaning adding spacers won’t affect your rebound.

Categories: Maintenance, Riding Tips

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