Tires Explained - Tired 101 - Tech

Treadwear
This is the rating that manufacturers provide for how long a tire should last. Using Uniform Tire Quality Grade standards (UTQG), a number is provided on the sidewall to indicate treadwear. The problem is that every tire manufacturer sets its own treadwear rating, meaning a 300 treadwear on one tire can still have a longer lifespan than a 300 treadwear rating listed on a different tire.

Despite this discrepancy, treadwear rating is a good overall indicator of the type of performance you can expect out of a tire. Based on our findings, 100 UTQG and below usually means the tire is meant for track duty, and even though it can be driven on the street, the rate at which it wears will be very high. A 100–200 UTQG rating will still provide ample grip with an acceptable wear life on the street and 200–350 UTQG tires are longer lasting, but give up some dry grip as a result. This is amplified even more with 350+ UTQG tires, which can provide exceptionally long tread life, but it’s at the expense of dry traction. In our experience, any tire rated over 350 UTQG will overheat quickly and lose grip when pushed beyond its design limits during aggressive driving on a track.

A lot of information is placed on the sidewall of a tire, including sizing — the first number stands for tire width, the second for sidewall height, the Z refers to the speed rating, the R stands for radial and the third for tire diameter (all measured in inches). The 96 in this case stands for the load index and the W is the speed rating. Note that the Z in front of the R is an older speed-rating placement that’s still used on this particular tire.

A lot of information is placed on the sidewall of a tire, including sizing — the first num

Speed Ratings
Speed ratings let you know what the safe and sustained maximum speed a tire can travel at. These U.S. government ratings are a good indicator of the kind of performance you can expect out of a tire. P-rated tires won’t have the grip or stability of H-rated tires, so if all-out performance is your goal, then aim for the highest speed-rated tire you can afford. Remember, though, a V-rated tire on a Honda Civic doesn’t mean it will be able to reach that speed, nor should you attempt to.

DOT R-compound tires have very shallow and strategically placed grooves that make them legal for street use, but don’t sacrifice much grip. They are purpose-built to provide ample grip for most street-legal cars taken to the track.

DOT R-compound tires have very shallow and strategically placed grooves that make them leg

All-season vs. UHP Summer vs. R-compound vs. Slicks
Common sense states that you shouldn’t drive a summer tire through the winter months, just like you really shouldn’t use an all-season tire at the track. That being said, the new generation of UHP all-season tires is very capable and has remarkable performance in dry conditions, even around a racetrack. We still recommend getting a proper UHP summer tire for track use, though, because less performance-oriented tires tend to overheat, scallop and chunk quickly under the harsh conditions found at a racetrack, not to mention provide less consistent grip.

Once you’ve become comfortable driving on a UHP summer tire at the track, we recommend stepping up to a DOT R-compound tire that provides uncompromised grip at the expense of streetability. Although these tires are still considered street legal since they’re DOT-approved, most R-compound tires will wear extremely quickly during normal road use, not to mention their wet performance is far from optimal. But put them on a racetrack, and they provide tremendous grip and consistency since the tread compound is designed to work best at the higher temperatures generated during track use. Depending on how soft the compound is, you can expect about one season’s worth of track use out of a set of R-comps (though this also depends on how many events you attend and how aggressively you use/abuse them).

Racing slicks are no-compromise, purpose-built, performance tires for the racetrack. They’re designed to provide the maximum amount of grip possible in a relatively short amount of time.

Racing slicks are no-compromise, purpose-built, performance tires for the racetrack. They’

Racing slicks are the crème de la crème when it comes to outright grip and on-track performance. They’re not street legal and rarely have any grooves (thus the term “slicks”). Their soft compounds provide maximum dry grip for a relatively short period of time. That’s why you see pro race teams going through a set of tires in a single session or two. Most weekend warriors don’t have the budget to run slicks, but we recommend trying them out if you ever have the chance because the grip level is just mind-blowing. (though the extra grip can be wasted on a car or driver that’s not able to fully utilize it).

Armed with this information, you should be able to make an educated decision as to what tire suits your needs the best. After that, there’s another world of education that you’ll want to learn to effectively dial in your tire at the track. Look for a future article on tire pressure and temperatures and how they can help improve your laps times.