How Dirt Bike Suspension Works (How To Tune And Set Up Suspension)

How Dirt Bike Suspension Works (How To Tune And Set Up Suspension)

Some people have the best dirt bike suspension in the world, but the problem is that most people don’t understand how it works.

Your dirt bike suspension is not worth much if you don’t know how to maintain it properly.

That being said, in this article, I am going to break down every detail on how to tune and set up your suspension for any style of dirt bike riding.

Dirt Bike Forks

The first step that you have to take for setting up and tuning your dirt bike suspension is the dirt bike forks. First, start with the front tire and make sure it’s inflated at a decent amount. A quick tip, I always keep my tires inflated to 13-14 psi.

However, take in mind that that’s my preference for off-road riding, that specific psi is great at preventing flats. For motocross riding, you can try inflating your tires to 11-13 psi.

While checking out your tires, make sure you also take a look at the front wheel. If it is installed correctly, the wheel should sit squarely within the fork legs.

In case it isn’t as described, then you can loosen the axle and pinch bolts and then tighten your axle nut, while afterward torque the left-size axle pinch bolts to spec.

After you compress the right fork, tighten the right pinch bolts until you’re sure the fork leg is in a decent and natural position.

If you checked all of that correctly, you will also need to adjust your rebound and compression damping, and you have to do that based on your preference.

Each dirt bike has its own manual, so before tuning your dirt bike suspension, check on the manual to see how the suggested factory suspension setup is.

Apart from that, the manufacturer’s manual is also going to show you how to adjust your fork.

After adjusting the fork, you have two options. Either raise or lower it in the triple clamps, and that will have an effect on the dirt bike’s geometry.

Nonetheless, you can always dial in your rebound and compression settings on the screws, or you can also identify these screws as clickers on the fork.

Just by the terms compression, you get the idea that it refers to the forks compression, and how much you want it to compress.

If you’re in for a softer ride, then you can do compression damping. Although there are some downsides to a softer ride because the dirt bike pitches under braking and bottoms out when riding.

The term rebound, on the other hand, refers to the original shape of the fork. Basically how much the fork snaps back to its natural position.

In other words, what you have to do is find a decent balance between these two settings. Finding a good balance means being comfortable while riding.

Each day before your ride, make sure to bleed the air out of your fork. You have to do this while having your bike on a stand, and your front wheel off the ground.

Dirt Bike Shocks

This is as important as the dirt bike forks because shocks are what support the rider’s weight.
Not only that, shocks also absorb impact and prevent the dirt bike from losing balance and making sure the rear tire stays in contact with the ground.

Same as you checked the fork, here you start with the tire as well. Again, make sure it’s properly inflated.

It’s important to note that heavy-duty tubes and mousses play a huge role in how your dirt bike’s suspension is.

That being said, logically you have to aim for the lightest possible setup, that way you won’t risk punctures.
What you have to do next is check your rear wheel, and make sure it’s well-aligned. Apart from that, make sure that the chain adjuster bolts are distanced in the same way of the swingarm.

In case they’re not backed out to the same distance, you’ll have to loosen your axle nut and then adjust the chain bolt on either side. After doing that, make sure you tighten the lock nut to secure it in place and retighten the axle nut.

Same as with the forks, before adjusting your shock, I recommend you take a look at the manufacturer’s factory settings if that’s possible.

It’s important that your suspension is fairly balanced between the front and rear, so the same things that we said about your fork apply here as well.

To get optimum comfort and rideability, make sure you adjust your compression and rebound here as well.

Other than that, adjust the suspension clickers without forcing the compression or rebound adjuster past the minimum or maximum extent of adjustment.

If you don’t follow these steps properly, you might cause internal damage to your dirt bike’s parts.

Dirt Bike Suspension Tuning

Tuning your dirt bike requires a little more effort than just turning a couple of screws. A method you can use to dial in your fork is by adjusting the weight and height of oil.

Thus, adjusting your fork oil height will have an effect on the air space in the fork, while on the other hand, it changes the damping elements in the second half of the suspension travel.

For your information, by adding oil you will stiffen the fork and increase the resistance on the bottom, and vise-versa, removing oil will soften the fork.

What you can do is add or subtract oil in 10cc gradients, and do that until you get the effect that you’re looking for. In practice, the fork oil can be added through the air bleeder using a small syringe.

However, to remove the oil will not be as easier, since you’ll need to remove the fork legs from the bike, and then hold them upside down until the oil is all drained.

Continuing now to the rear part, make sure that you have the proper rate spring that holds up the rider and the bike. As it is common, most bikes are more suitable with 95-115mm of sag with the rider on.

Nonetheless, after getting the rider sag, what you should do is check the static sag that the bike has without the rider.

Most static sag’s range from 25-45mm, but if it’s less than 25mm, you’ll definitely need another spring, a stiffer one.

If the static sag is greater than 45mm, then it’s the other way around, you’ll need a softer spring.

How To Adjust Dirt Bike Suspension For Your Weight

I have been there, and I know how frustrating it can be not knowing how to adjust the dirt bike suspension. But it’s not as complicated as it seems, what you’ll need to do is setting the sag.

By doing this, you’re going to be changing the amount of how much the dirt bike moves downward when the rider is on the bike. Even though you can do this alone, to avoid problems, I recommend you set the sag with a friend, two people are always better for this process.

First, you’ll have to measure the sag, and you can do that using a static measurement. Place the dirt bike on a stand, leave no wheels on the ground, and start measuring from the middle of the rear axle to a fixed point.

After you know the measurement, what you should do is put your front wheel and stand on the pegs. This is where the second person gets into the spotlight, he/she needs to do another measurement from the fixed point on the rear of the bike.

Now this difference that we see between your measurement and your friend’s measurement is called the sag.

It’s important to note that there’s no correct measurement for this since it depends on plenty of factors such as rider preference, the bike itself, or the trail that you’ll be riding on.

Now that you’ve reached this point, you’re ready to adjust your sag. To do that you can either use a hammer and punch, or some tool if the manufacturer has included one with the bike.

After loosening the shock spring lockring, to increase or decrease sag all you have to do is turn the spring preload ring.

By doing this, turning your dirt bike’s suspension and adjusting the sag is going to provide you with an exceptionally comfortable riding experience.

That’s pretty much it, and as we reached the end, I’d recommend you stay on top of the maintenance with your dirt bike, change the fork oil and anything else that needs to be taken care of.

By doing all of that, your dirt bike will last for many years to come, and to get to the point of the article, your suspension performance will be as consistent as it gets.