How to Read a Motorcycle Tire | Sidewall Codes Explained

Motorcycle tire sidewalls list size, load, speed, rotation, and date codes in a set pattern — learn the order and what each symbol means.

Standing next to your bike, the collection of letters and numbers on the tire’s sidewall can look like a secret language. But “how to read a motorcycle tire” comes down to one systematic pass: the size string first, then load and speed ratings, then the build markings, and finally the age code. Once you know the order, a quick glance tells you everything about what’s mounted on your rims — and whether it’s time to replace it.

The Size String: What Each Number And Letter Means

The size string is the main event. On most modern tires it looks something like 120/70 ZR17, and each element carries a specific meaning. According to Dunlop’s guide to reading a tire sidewall, these positions break down like this:

Read these five figures as one phrase: a 120-millimeter-wide radial tire with a 70-percent profile, designed for a 17-inch rim. The Z sits with the speed rating rather than the size — it tells you the tire can handle sustained high-speed riding, not how wide it is.

Load, Speed, And Rotation Markings

The load index and speed symbol work as a pair. A load index like 73 means the tire can carry 805 pounds (365 kilograms) at maximum inflation, while the speed symbol — the letter like H, V, or Z — states the fastest speed that load can be carried under specified conditions. Neither number stands alone; a tire rated for a heavy load at low speed may not handle that same weight at highway velocity.

Build markings sit nearby. TL means tubeless, M/C designates a motorcycle tire, and a directional arrow on the sidewall shows which way the tire must rotate once mounted. If that arrow points backward, the tire won’t grip properly in the wet and will wear unevenly. When you’re sizing up a new rear tire, you’ll also spot the model name — something like Pilot Power 3 on a Michelin — which confirms the specific compound and tread pattern you’re buying. If you’re in the market for a common sportbike size, our roundup of the best 180/55 ZR17 motorcycle tires breaks down the top options side by side.

The DOT Code: How To Read Your Tire’s Age

The Tire Identification Number (TIN) is the tire’s birth certificate. The full DOT string tells you who manufactured it, where, and when — but the part that matters most is the last four digits. Those numbers follow a WWYY format: the first two digits are the week of manufacture, and the last two are the year. A code ending in 2323 means the tire was built in week 23 of 2023.

One catch: on many motorcycle tires, the full DOT code appears on only one sidewall, so you may need to roll the bike forward to see it. Also watch for a three-digit ending — that marks a tire made before 2000, and one that old is well past any reasonable service life. Regardless of tread depth, most manufacturers recommend replacing tires after about five to six years from the date code, since rubber compounds harden and lose grip as they age.

FAQs

Where is the tire size located on a motorcycle tire?

The main size string sits on the sidewall, usually in the largest, boldest lettering. It follows a format like 120/70 ZR17 and includes width in millimeters, aspect ratio, speed symbol, construction type, and rim diameter in inches. If the sidewall looks crowded, the size is always the most prominent grouping of numbers and letters.

How do I check the manufacture date on a motorcycle tire?

Look for the DOT string on the sidewall; the last four digits are the date code. The first two digits are the week of the year, and the last two are the year itself. A code ending in 2323 means the tire was made in week 23 of 2023. A three-digit ending means the tire predates 2000.

What does TL mean on a motorcycle tire?

TL stands for tubeless, meaning the tire is designed to seal directly against the rim without an inner tube. Most modern motorcycle tires are tubeless, but if your wheels have spokes rather than cast construction, they may require a tube-type tire or a tubeless conversion kit with a special rim band.