At SuperATV, we make all of our A-arms and radius arms adjustable. That gives you total control over your machine’s camber, toe, and caster. But why should you care? What’s the point of adjusting your suspension outside of the factory specifications?
Let’s take a look at what camber, toe, and caster really are, how you can adjust them, and why you might want to.
Camber is the inward or outward tilt of the tires when viewed from the front of of the machine. Having the wrong camber can really ruin your ride, both in terms of the way driving it feels and in terms of actually wrecking because your traction is so bad.
So what’s the difference between crappy camber and the camber you crave? Let’s take a look.
Zero camber is what you might think of as the default camber. It’s a good starting point for a typical rider.
With zero camber, your tires are straight up and down when your machine is sitting on the ground. It gives you good traction most of the time. It’s the camber you want if you’re using a Ranger or similar side-by-side for work, or plan on keeping it relatively slow for most of your rides.
However, once you start getting your speed up on the trails, zero camber starts to hold you back rather than help you.
Negative camber is when the top of your tire leans in toward the center of the vehicle. And having 2 or 3 degrees of negative camber helps immensely with traction on corners.
Here’s why: When you make a fast turn, the bottom of your outside wheels get pulled in toward the machine. If you have zero camber, that pull causes you to ride on the outside edge of your tire for the duration of the turn, which gives you much less traction.
If you have a couple degrees of negative camber, the turn pulls your tire so that the bottom is flat against the ground during the turn, which gives you maximum contact with the ground and more traction when you need it most.
For high performance machines and high speed riding, negative camber is the way to go.
You can also get negative camber if you add weight to your machine from a cooler, extra rider, or from accessories like cab enclosures and reinforced cages. So keep that in mind if negative camber isn’t something you want.
Positive camber means the top of your tires are leaning out away from the machine.
You don’t want positive camber. You might like to think of your UTV as a farm tractor’s cousin (some of you put tractor tires on it after all), but all positive camber does is give you less traction and causes your tires to wear unevenly.
You get positive camber naturally when you lift your machine and sometimes when you upgrade shocks. The main thing you should know is that you don’t want it.
The first thing you need is a set of adjustable A-arms and possibly radius arms depending on your make and model. Your stock A-arms won’t do—they’re not adjustable. Luckily, adjustable parts aren’t hard to come by. All SuperATV A-arms and radius arms are adjustable and so are many other aftermarket suspension parts.
Our A-arms are set to OEM specs right out of the box, so if you’re looking for OEM camber, you’re already good to go. As you make adjustments, keep in mind that the weight of the driver will give you a little bit of negative camber naturally. It’s not always noticeable, but some choose to compensate for it with a smidge more positive camber.
With your machine on the ground and all your tires inflated to the same pressure, grab a carpenter’s T-square and butt it up against the side of your tire. That will tell you quickly whether you have positive (top leaning out), negative (top leaning in), or zero camber. You’ll also be able to tell which way you need to make adjustments. If you use an angle gauge, you’ll know how many degrees you need to go in or out.
Lift your machine and remove your lower A-arms only. Lower SuperATV A-arms have adjustable pivot blocks.
Loosen the jam nuts on your pivot blocks so you can thread them in or out. If you want more negative camber, thread them out. If you need more positive camber, thread them in.
Two full turns of the pivot block changes your camber by about 1 degree. We recommend about 2 degrees of negative camber for high speed cornering.
Radius arms work similarly. Most stock and aftermarket radius arms have adjustment built in. We recommend adjusting the lowers to set your camber.
Before you go measuring your new camber, put your machine on the ground and roll it back and forth. This settles the suspension and shows you what your true riding camber will be.
Repeat these steps until you have your desired camber, then take it out for a spin!
Keep your machine on the lift and make adjustments and measurements while it’s still in the air. Just keep in mind that with the suspension at full drop, you’ll have roughly 2 degrees more positive camber than you’ll have on the ground.
Keeping it lifted allows you to install your lower A-arms up with just bolts to rapidly adjust and check easily. The only downside is that you still won’t know if you got it exactly the way you wanted until you put the machine back on the ground.
Toe is the direction your front tires point. If they point out, then they are toe-out. If they point in toward the machine, then they are toe-in. Toe is controlled by your tie rods.
Too much toe in or out can cause major wear on your parts, as well as make handling more difficult. That could lead to tie rod end failure, wheel bearing failure, and other issues.
Every side-by-side has different requirements for toe. Usually, they’ll come with a small amount of toe out from the factory. There’s usually not a good reason to stray from the factory settings, but if you change suspension parts or haven’t checked your toe in a long time, your alignment might be off.
Make sure your tires are both inflated to the same psi, then park your front tires on a slick surface to make adjusting easier. You could use cardboard, a plastic sheet, or something similar. You’ll need a helper or a tool to hold the steering wheel straight at this point.
Loosen the jam nuts on your tie rod and turn it by hand or with a wrench if needed to thread or unthread both tie rod ends simultaneously. If you look down the side of your tire as you turn, you can line up the edge of your front wheels with your rear wheels to get them pointed straight forward.
Once you straighten both wheels, take a tape measure and measure the distance between the centerline on both your tires. If you get the same measurement when you measure from the front and rear of your tires, you know you’ve got them perfectly aligned together. Make sure you roll your machine back and forth to settle your machine between each adjustment.
When you’ve confirmed that they’re both pointing the same direction, and that direction is straight ahead, you can tweak your toe if you want to. Different vehicles are built for different toe-in or out, so you’ll either need to look up your factory toe or experiment a little bit. An eighth inch in or out is about all you’d need. You can tell if your toe is too far in because it will cause your suspension to raise the front end as you drive. If it’s too far out, it will pull the front end down.
If you imagine an invisible line connecting the ball joints on your hub, that’s your steering axis. The tilt of your steering axis is your caster. Good caster gives you great control. Bad caster can either make your steering rack feel like it’s filled with rocks or make it feel so squirrely that it’s difficult to stay in control.
Normally you don’t need to mess with caster, but if you get bigger tires, or just enjoy fine-tuning every aspect of your machine, you’ll want to take a look at it.
The main culprit behind bad caster is bigger tires, and here’s why:
The upper and lower ball joints on your vehicle are never straight up and down. The upper is always a few inches behind the lower. This is super important because it means that when you turn, your pivot point is slightly ahead of your tire’s contact patch (the part of the tire that actually touches the ground).
That makes the ground pull your tire backwards and your wheels tilt over when you turn. That’s what causes your tires to straighten out when you let go of the steering wheel.
The angle between your steering axis and your contact patch dictates the way your vehicle handles more than anything else. If your steering axis is flatter, your wheels will be harder to turn, but you’ll have more stability. If it’s more straight up and down, it’ll be easier to turn, which will require more work from the driver to keep things stable. Larger tires really throw it out of whack.
Bigger tires increase the distance between your contact patch and your steering axis, which makes your wheels harder to turn. So when you upgraded your machine to some monster 40” tires, maybe it wasn’t just the weight that made them harder to turn, but rather your caster.
Even with bigger tires, you should worry about your camber and toe before you worry about your caster. It’s the last thing you need to worry about when you’re adjusting your alignment.
Make sure your tires are both inflated to the same psi, then lift your machine.
You have to remove your lower A-arms in order to make adjustments. SuperATV always puts the adjustable pivot blocks on the lower arms. Other brands may have their adjustment located elsewhere.
Thread the front or rear pivot block in or out 1 or 2 turns. Threading the front pivot block in, or the rear pivot block out, will make your steering axis flatter and give you more stability. Doing the opposite will make your steering axis more straight up and down, which will make steering easier. A few degrees makes a huge difference, so start with small changes. Make sure both sides have identical caster.
Reinstall your lower A-arms and roll the machine back and forth to settle your suspension.
Take it for a test drive! It’s hard to say exactly what you should set it to—every machine is different and has a different feel. So drive it, see how it feels, and make more changes as needed.
Getting everything adjusted just right gives you a smoother ride, better control, and longer lasting components. So don’t skip it! Keep your eye on changes to your alignment so you can proactively maintain your machine. And if your alignment is off, be sure to make sure your ball joints, tie rod ends, or other suspension components aren’t wore out.
The point: keep everything in good shape and you’ll have a good ride!