Posted on January 06 2022
Modern mountain bike suspension often has a wide degree of tuneability, allowing for riders to make or break the perfect setup for the best performance outcome. In this today's blog, we're outlining the importance in order of what needs to be considered when setting up your suspension for the best possible outcome, or for that very first shred. This is not a setup guide, but it is a guide for what to consider, in order of importance to get you started.
Whether it be an air-sprung or a coil-sprung suspension fork or shock, Spring is the fundamental number one to get set up properly first, above anything else. After all, the 'spring' is the dominant force in every suspension system on the market, and correct setup is crucial for setting for all the other adjusters. The 'spring', whether it be coil or air, provides the greatest degree of change in a suspension fork or shocks feel, over anything else. The spring is set based on 'sag', which is a term referring to how much the suspension compresses with our weight on it. Sag is usually measured in the range of 20-35% of a suspension's total travel, for the best outcome. here's a great setup guide for setting sag.
2) Rebound (Low speed rebound - LSR).
The process of setting up low speed rebound correlates directly to the setup of the 'spring', whether it be a coil or air fork/shock. Low speed rebound (LSR) is the most common form of rebound adjustment found on every suspension system, and with an increase in spring pressure or spring rate, more LSR is used. Ie, more rebound damping is applied through the adjuster as the spring rate is increased. (normally the 'red' clicker, rotating it clockwise for more damping). Heavier riders are more likely to use a higher spring rate for their air or coil suspension, and hence require more rebound damping to control that higher spring rate, and vice versa for lighter riders.
Air volume has become one of the fundamental setup factors to get the best outcome from an air-sprung fork or shock. The internal fork/shock's volume is adjusted by adding or removing volume spacers from the air spring chamber. More volume spacers inside an air spring results in a more progressive feel - ie, the suspension starts to feel firmer sooner in its travel. Less volume spacers inside an air spring results in a more linear feel - ie, the suspension feel remains consistent through the majority of the travel. The issue with a linear feel is that the suspension doesn't support the rider for the bigger hits as well as a progressive feel does. Hence by adding volume spacers as a way of tuning, users can achieve a happy medium of a linear initial travel, followed by a progressive 'ramp-up' towards the end of the travel, depending on how many volume spacers are installed. Adjustment of volume also allows us to use lower air spring pressure in order to achieve the best possible degree of sensitivity, without getting harsh bottom outs on the bigger hits. Adding volume is an important factor since it effectively results in an increase in sensitivity, which means an increase in traction. More traction - more fun.
4) Compression (Low speed compression - LSC )
Low speed compression is getting into the world of fine-tuning. Many suspension systems do not have the ability to adjust low-speed compression (LSC), but for those that do, adjusting LSC can allow us to refine the characteristics of the spring, rebound and volume settings. LSC adjustment will allow you to dial in or dial out how much pedalling induced movement is transferred into the suspension, and also how much sensitivity the suspension provides on general trail undulations. It's used as an adjustment to refine the air spring pressure. For example, there's no point using all or more of a suspension's range of LSC adjustment if the spring rate is too soft. In that case, most suspension systems would provide a better performance outcome with a slightly higher spring rate (ie, more air, or a heavier coil spring), and less LSC damping. Additional LSC damping can also help hold a fork up higher, especially during hard or aggressive front-braking.
5) Compression (High speed compression - HSC )
High speed compression is generally only found on the higher end suspension items, like Fox's GRIP2 damper or the Rockshox Charger RC2 series for example. High speed compression controls the rate of compression that is applied through the suspension damper during a heavy hard hit, or a square edge type of impact. Having the ability to adjust HSC is a refinement that allows for a more supported feeling during those harder hits. Whilst more aggressive riders, downhill and enduro racers will see a degree of benefit to having the ability to refine HSC, in very general terms, the average rider amongst us can certainly live without it.
6) Rebound (High speed rebound - HSR).
High speed rebound is generally only found on the higher end suspension items, like Fox's GRIP2 damper, and X2 shocks for example. High speed rebound controls the rate of rebound that is applied through the suspension damper after a heavy hard hit, or a square edge type of impact. Having the ability to adjust HSR is a refinement that allows for a more supported feeling following those harder hits and without getting bucked upon hard landings. Whilst more aggressive riders, downhill and enduro racers will see a degree of benefit to having the ability to refine HSR, in very general terms and to repeat the above, the average rider amongst us can certainly live without it.