It’s easy to get overwhelmed by the number of options when shopping for tires. That’s understandable. Between tread design, DOT compliant, specialized tires, rubber compounds, and the type of riding you do, a lot needs to be considered before you can choose a tire. That’s why we put together this guide to help you sort through some of the commonly asked questions and essential pieces of info you’ll need to know before shopping for off-road tires.

Keep in mind that this guide is specifically for dirt bike tires and won’t cover tires for sport, cruiser, or street bikes. And although we briefly touch on DOT compliance, specific information needed for road tires will not be covered. Don’t forget to check out our full selection off-road and dirt tires here.

Sizing and Tire Info

Understanding Your Tire’s Size

We’ll start with the information printed on the sidewall of the tire. The most noticeable info (apart from the brand and model of the tire) will be the tire size.

sidewall tire size information
Figure 1: Here’s an example of the typical format used for tire size information on a tire’s sidewall.

Typically the tire size is arranged in a set of three numbers as seen in figure 1. These numbers give the measurements of three dimensions that every tire has:

-The first number is the width of the tire from sidewall to sidewall in millimeters.

-The second number is the sidewall height (also known as the aspect ratio) that’s represented as a percentage of the tire width (the first number). The example in figure 1 has a sidewall tire’s 120mm width, which ends up being 96of sidewall height.

-The third number is the inner diameter of the tire in inches, which will be the same size as your rim. For example, a 19″ tire will only fit a 19″ rim.

 

Pretty easy, but there are some notes to keep in mind:

-Some tires have a sidewall that’s taller than the width, so a 100/110 or 100/120 tire is possible and common. The number is still a percentage of the first and won’t affect the tire’s mounting or fitment.

-An 18” tire height will be very similar to the overall height of a 19” tire. Remember, the last number is the inner diameter, not outer diameter, and that inch of difference is made up in the sidewall height.

-In most cases, you may be able to go with a different width and/or aspect ratio on the tire you choose (refer to your owner’s manual for recommendations), but you can’t go with a different rim diameter.  If you have a 19” rim, you have to go with a 19” tire.

-Some tires are measured in inches instead of millimeters. The numbers still denote the same measurements, though some tires measured in inches do not specify sidewall height/aspect ratio. Tires measured in millimeters and inches are interchangeable without any issue.

Other Info on the Sidewall

DOT Stamp

Next is the DOT stamp. Also found on the sidewall of the tire, the DOT stamp doesn’t provide much info on its own, but it does certify that the tire has been approved for on-road use in the U.S.A. Typically the marking says “DOT” or “DOT Approved” while tires not approved for road use may say something like “not intended for highway use.” So if you see a lot of pavement on your adventure or dual-sport bike, make sure your tires have the DOT stamp. See all your options here.

Here are two examples of what a DOT certification stamp may look like on a tire’s sidewall.

Direction of Rotation

It’s also crucial to check the sidewall and see if your tire is directional—meaning it’s designed to be mounted so it rotates in a specific direction. You’ll find an arrow on one or both sidewalls that points in the direction of forward rotation once the tire is mounted, if the tire is in fact directional.

Example of what a directional arrow may look like on the sidewall.

Finding the Tire’s Lightest Point

One of the last things learned from a tire’s sidewall is where the lightest point of the tire is. Look around the sidewall and you should find a stamp/paint mark that’s been manually applied to the tire at the factory. This mark may be a quality control stamp or a simple dot. Either way, the mark should be on the lightest part of the tire found when it was balanced at the factory. This is handy because if you put your rim lock or tube valve next to the stamp, the weight will help balance the tire out.

how to find the lightest part of a tire
Marks/stamps indicating the lightest part of the tire will differ in appearance. This one is a simple circle stamped in yellow paint.

Tire Types and Tread Designs

Another bit of info that’s crucial is a tire’s tread design, rubber compound, and area of specialization—i.e. what type of tire it is. All of these play a big part in tire performance and can make the difference between having a great ride or going nowhere because you have zero traction.

Starting with the classic MX knobby seen on most off-road bikes, these are usually divided into three types—soft, intermediate, or hard—based on what terrain they’re meant to be used on. However, that doesn’t mean a hard-terrain tire will have a hard rubber compound. These designations only tell you what terrain the tire is good for.

Soft-Terrain Tires

If a tire is labeled as a soft terrain tire, it’s made for loam, loose gravel, and other soil types that have minimal structure. Soft-terrain tires have tall, aggressive lugs to help bite down into the dirt and widely spaced tread patterns that promote self-cleaning (the tires ability to throw off stuck dirt as it rotates). Despite the name, soft terrain tires are typically made from a harder rubber compound. These hard compounds work well since they let the tread lugs keep their shape as they push deep into soft terrain. But the hard rubber is not great on hard terrain because the tread will be too stiff, resulting in lugs/knobs being ripped off the tire—commonly known as chunking.

2018 yz450f on track
Because it’s a dedicated track bike that will only ride on soft dirt and manicured loam, this 2018 Yamaha YZ450F will probably wear soft-terrain tires (like the Dunlop MX3S pictured) most of its life.

Hard-Terrain Tires

Hard terrain tires are on the other side of the spectrum. They’re designed to be used on tightly packed soil and hard surfaces like bare slick rock and well-worn tracks. They have a tread pattern that’s more tightly spaced compared to soft terrain tires, ensuring as much rubber touches the ground as possible. Hard-terrain tires also use a soft rubber compound that has more flex in order for each lug to deform, grab onto the terrain, and increase traction.

In conditions like these, it’s crucial to run a hard-terrain tire to both find traction and keep the tire from ripping apart.

Intermediate/Medium Terrain Tires

Right in-between hard and soft terrain tires are the intermediates, and they split the difference exactly like you would think. Intermediate and medium terrain tires work well on a variety of terrains, making them the most popular and frequently picked type of tire. Medium terrain tires have a mid-grade rubber compound that balances stiffness with flexibility. They also have average height lugs and moderately spaced tread for good dirt ejection and a nicely sized contact patch.

2017 450rx bridgestone battlecross tires
This 2017 Honda CRF450RX is an off-road cross-country racer that’ll see a wide variety of terrain conditions. That makes the Bridgestone Battlecross X30 Intermediate tire it’s wearing a perfect match for the bike’s use.

Specialized Tires

Outside of the standard MX knobby, there are also specialized tires made for specific types of terrain and different kinds of riding.

Desert Knobby Tire

A derivative of an MX knobby, a desert tire is specifically made to withstand harsh and rocky desert terrain. These desert-specific options have tall lugs that are evenly spaced—similar to an intermediate tire—so they dig in to loose rock and dirt. More importantly, these tires have a specialized rubber compound and a stiffer sidewall that help it cope with desert hazards like jagged rocks, loose shale, and sharp edges that can easily rip apart other types of tire.

Trials Tire

Trials tires are made to deliver the most amount of traction possible on hard, slick surfaces. Originating from trials riding where riders jump their bikes across obstacles with seemingly unnatural skill, the trials tire has become a popular choice for riding single-track, enduro, and technical terrain. The tires have a uniform tread pattern that’s tightly packed, a flat crown, and flexible sidewalls. They also use a very soft rubber compound that can almost feel sticky to the touch. These characteristics give trials tires a very large contact patch that can flex and deform in order to grab onto terrain—resulting in massive amounts of traction. The increased traction makes trials tires great for technical terrain and hard-packed trails, though that traction comes at the cost of cornering performance. Watch this video for more info on trials tires.

Hybrid Tire

Hybrid tires are a cross between knobbies and trials tires, with the main goal being to deliver the traction of a trials tire and the cornering of a knobby. Looking at a hybrid tire, you’ll see they have a rounded crown, lots of knobs/tread on the shoulder, and blocky lugs that are more spread out compared to a trials tire. What you won’t see is that hybrids have a more flexible sidewall than MX knobbies and a soft rubber compound like a trials tire. These design choices make hybrid tires grip just as well as trials tires on the trail, but they corner much better than trials tires—almost as good as a traditional knobby. That makes hybrids nearly perfect for all sorts of trail riding, whether it’s tight, technical terrain or high-speed turns. Watch this video for more info.

This side-by-side comparison illustrates the difference in tread design between a desert tire (Maxxis Maxx Cross Desert LEFT), a hybrid tire (Shinko R505 Cheater CENTER), and a trials tire (Pirelli MT43 Pro RIGHT).

Paddle Tire

Paddle tires are a unique option that are purpose-built to be ridden on sand, and not much else. Instead of tread blocks, a paddle tire has large scoops or paddles that work like shovels to grab sand and propel the motorcycle forward. This design only works on sand and produces a bumpy, uncontrollable ride on any semi-hard terrain. If you’re headed to the dunes, nothing will put your bike’s power to the ground like a paddle tire. But if you’re planning on riding somewhere else, save your paddles for the dunes and use a different tire.

cst surge paddle tire
One of the most popular paddle tires is the CST Surge C7220.

Sand Hybrid

Sand hybrids are another tire that combines characteristics from two specialized tires to get the best of both options. In this case, sand hybrids take the best from knobbies and paddle tires. Sand hybrids still have distinct scoop or paddle shapes on their tread, but the scoops will actually be composed of individual lugs as opposed to the one-piece molded scoops of a traditional paddle tire. The paddles on a hybrid let the tire scoop sand just like a true paddle, but with more closely spaced tread and aggressive shoulder lugs, sand hybrids corner like a knobby and can ride on harder surfaces that would destroy a true paddle. These traits make sand hybrid tires popular for sandy, loose MX tracks like Southwick, and ideal for sandy areas that have both harder-packed trails and wide-open dunes.

michelin starcross 5 sand tire
The Michelin StarCross 5 Sand Tire is a hybrid sand tire with the scoop shape of a paddle and the tread concentration of a knobby.

Tire Pressure

Lastly, we’ll talk about psi since it has a huge effect on the performance of a tire. The first place to go for a baseline recommendation is the service/owner’s manual or the informational badging on the bike itself. Information found there should give you a good idea of what psi to run. However, a good working psi can change depending on how you ride and what type of terrain you’re on.

2017 crf250l rally off road
If you’re covering a lot of ground on and off road on something like this 2017 CRF250L Rally, changing terrain may mean you’ll need to adjust your tire pressure a few times during a single ride.

On average terrain, most knobby tires can run around 12 to 15 psi—a little lower if you want more traction and flex from the sidewall,  a little more if you want to avoid pinch flats or rim damage. Just remember, every tire has a maximum psi recommendation printed on the sidewall. This pressure should not be exceeded when installing the tire and setting the bead (watch our video on how to change a dirt bike tire for more info). Always refer to your owner’s manual for recommended pressure settings. There are other tire, tube, and accessory options that can change the psi you run. You could go as low as 2 to 3 psi in the case of Tubliss, or you could not deal with psi at all in the case of foam inserts (Bib Mousse). We won’t cover these here, but we do cover them in our video about preventing flats.

off road tire information guide

Comment

Tell Us What You Think

That should be all the major points to think of when shopping for dirt and MX tires. If we forgot something, let us know about it in the comments below. We’d also like to hear what important info you look for when evaluating a tire. Leave your thoughts below.