Correctly setting up the suspension is crucial for proper handling of your bike. You may have the most expensive, best bike in the world, but if its suspension is set up wrong, you may as well ride a unicycle.
It may seem like dark magic only tamed by those with special powers, but we will make it easy with some simple steps. We will set your spring rate using sag, talk about rebound damping controls the fork, and what compression dampening does for your ride.
Sag refers to how much travel is used when a rider's weight is placed on the bike. Most bikes usually like to be sitting from 25% to 30% in their travel. The correct sag will retain the bike's geometry, have maximum traction all the time and use the full travel effectively. Too much sag and the cycle will bottom out too often. Too little, and it won't use all the travel effectively, leading to a harsh ride.
Setting sag is super easy, and it can be done in 8 easy steps:
Using your shock pump, pressurize your suspension. Let's start with your weight in kg as a pressure in the fork and your weight multiplied by 2.5 in the rear.
Lean your bike up against a wall in a way you can support yourself while sitting or standing on the bike.
Before hopping on, put on all your riding kit. And make sure no compression dampening or lockout is turned on.
Starting with the front fork, we want to make sure your sag indicator ring is up against the fork seal before you hop on the bike.
Throw a leg over the bike and put your feet on the pedals. While leaning against the wall, get in your riding or "attack" position.
When you are in that position, get a mate to make sure the indicator ring is still on the seal. If you are alone, gently reach down and check the o-ring without leaning too far forward.
Gently sit back down on the saddle and hop off the bike without disturbing the fork.
Measure the sag with the sag indicator on the fork or a ruler. We have a sag measurement chart with the measurements below.
If you have too little sag (the suspension isn't deep enough), you will need to remove some air. If it is sitting too deep and has too much sag, you will need to add more air. We recommend adding or removing 5 psi at a time because it will result in less over/under see-sawing.
Sag is an indicator of your spring rate. While some bikes have recommended sag ranges, it can be a personal preference for your riding style and terrain. Using sag as a guide to measuring your ride's stiffness is fine, but you need to ensure it is measured in the same way, in the same style every time for consistency.
If you find your ride harsh and bumpy over the rough stuff or hard to gain traction, your suspension may be too hard. A good indicator of this is if the sag o-ring isn't at full travel after a ride. Suppose the bike feels lethargic, unresponsive, and blowing through travel easily. In that case, you could be pushing the bike beyond its current spring rate, and trying a lower sage may improve how the bike feels. It is good for riders to experiment with different sag rates to determine how they like their bike to ride.
If your bike is equipped with air-sprung suspension, then you can use volume-reducing "tokens" to tune your spring rate. If you like suspension to be soft at the start of its travel but don't want to experience harsh bottom outs, tokens will support the last part of the travel. If you are running tokens and find the suspension feels a bit harsh, you aren't using all the travel; even with a high sag number, you may have too many tokens. Again, we recommend that you experiment with these settings and find the right balance for you.
What are those knobs for? Let's talk about the red knob at the bottom of your forks. Depending on your fork model, you may have one or two of these at the bottom of your fork. These knobs adjust the speed at which the fork returns from being compressed.
If the fork is too fast, the front end of your bike will feel like a pogo stick. If the fork is too slow, the fork won't return to sag point before the next hit, and the fork will "pack down." These will lead to a bike with hard-to-control steering, and an uncomfortable feel through the bars. If the bike feels erratic and unstable through the front wheel, then your forks are too fast. If you feel the bars dropping and the cycle pitching forward, it may be too slow.
A good base setting is to jump on the bike after setting sag, bounce up and down in the street. When you push down, the fork should compress but, as it comes back, it should return to the sag point quickly. Look down at your fork (when safe) as you bounce. If you see it return past the sag point and compress back into its ride height, it is too fast. If it's slow, you will see the fork stay down too long and not come up. Turn the dial until you feel comfortable with the setting.
Compression adjustments control the force required to compress the fork separately from the spring. Compression dampening doesn't care where you are sitting in the fork's travel. It is consistent throughout the stroke. If you feel your fork is compressing (going into its travel) too much during pedalling or compressing in a corner, add some dampening. If the fork isn't compressing easily enough, it will feel harsh in the chatter.
Some forks have multiple knobs for both rebound and compression, usually 2 per end. Often referred to High Speed and Low-speed adjustments. This use of fast and slow doesn't refer to how fast you are traveling along the trail. It refers to how fast your forks are traveling up and down. High-Speed damping affects the fork in times the fork moves up and down at a high velocity through rock roots and harsh landings. Low speed controls the suspension movements in slow circumstances like corners and jump lips when the suspension travels through its travel slowly.
Bracketing is the most effective way to set up your suspension. Bracketing is the practice of taking each setting individually and finding the correct setting via back and forth adjustments.
The first thing to make this procedure effective and easy is to find a short 1-1.30 minute section of trail you ride regularly. Ideally, this section should have a corner, some rocks or roots, a jump and a good pedal to get started. The idea is to hit the features confidently and without fatigue.
We will go through each setting one at a time, fork rebound, fork compression, shock rebound, and shock compression. Firstly, slow your rebound as slow as possible and do a run at 70%. Next run, speed it up and do the same, don't go too hard as the fork may feel too erratic. The purpose of this first exercise is so you can identify the effects of each setting adjustment on your bike. Sometimes one or two clicks aren't enough to feel a big difference, so this drastic change will help you in the future.
Once you notice the difference for each setting and how it affects your bike, you want to go to the middle setting or a factory-recommended setting. With that setting, you want to up the pace and do a run at 90%. If it doesn't feel how you like, do a run with 2 clicks more dampening. If it feels worse, then take 4 clicks of damping-off (2 clicks out from the original setting). That setting may turn out to be better than the original setting. Take it off 2 clicks more and do a run.
This process of doing a run at different positions is called bracketing. You start at a base, keep adjusting in a direction until it feels bad. Then you go back the other way too far. With every swing of the settings, you narrow the number of clicks you change. Eventually, you will be down to 1 or 2 clicks from your Goldilocks setting. You will have a bracket of one or 2 clicks that can be adjusted depending on the tracks.
Go through each one of the settings on your suspension and do the same process. You will notice some settings affect others. Finding the balance of all the suspension settings is best and compromising some settings for others is common. We recommend spending time on this part of setting up your suspension, as it will get your bike dialled from the get-go.
To wrap up, it can take time to find the setting, and sometimes it may need a change for some riding circumstances. One common time it needs to be changed is as you get faster or hit bigger obstacles with confidence. However, doing the above process will get it dialled again. Suspension is critical to your bike's performance, and it can completely change how it rides. Taking time to understand your bike and how it works will benefit your riding immensely.
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