Buying tires for your motorcycle online can save you a ton of cash. But doing this requires you to make sure you get the right ones for your bike. To help you out, we’ve put together this guide about how to read a motorcycle tire, so you can be informed about not only the tires on your bike now, but what tires you need to replace them.
Stretching the life of a motorcycle tire is NOT the way to save money. Quick, scroll down before you crash!
There are two steps to getting the right tires:
- Choosing the right tire type based on your needs, and
- Determining the correct size for your application.
Choosing the Right Tire Type
To choose the right tire type, you need to examine your bike and riding style to determine which type is appropriate for you. There are four general designations: cruiser, street, dual-sport/ADV, and dirt. Choosing the family of tire you need is the easy part; it becomes more complicated once you get down to specifics, like brand, compound, speed rating, etc. (and at some point it will become simply a matter of personal preference.)
Pirelli race tires, ready to ship. Beautiful.
Choosing the Right Tire Size
To choose the right tire size requires that you have knowledge of what the code designators printed on the side of tires mean, and that’s what we’re here to help you decipher.
There are three different methods manufacturers use to designate tire information “alphanumeric, standard inch, and metric”, but the industry standard today is the metric system. The alphanumeric system is very infrequently used, and the standard inch system is no longer used (but may need to be converted to determine what to use as a new replacement.) The vast majority of tire manufacturers use the metric method, and that’s what we’ll be focusing on.
The metric system has five main components, and they are all printed on the tire sidewall. Some are strict measurements, others are codes that indicate something, so we’ll explain them all.
- Section Width: measurement of the width of the tread, in a straight line from one side to the other. Almost always a three-digit number.
- Aspect Ratio: the ratio of a tires width as a percentage of its height; the higher the number, the taller the tire. Usually a two-digit number.
Hint: to determine the exact height of a tire, simply multiply the width by the ratio expressed as a decimal (so a ratio of 60 would be converted to 0.6.) So with a 130/90 tire, multiply 130 X 0.9 to arrive at 117mm.
- Rim Diameter: measurement of the rim, from one lip to the other, in inches.
- Load Rating: a code designating the weight a tire is designed to bear, ranging from low 20s to high 80s (see chart below.)
- Speed Rating: an alphabetical code designating the speed a tire is designed to run at safely, when properly inflated and loaded, from J-Z. Not always ordered alphabetically, and can be a little confusing (see manufacturer information.)
Also found on tires will be a “born-on date”, which indicates the tire’s date of manufacture. This will be a four-digit code: the first two digits indicate the week of the year it was made (1-52), and the last two digits indicate the two digit year it was made. (So a tire with a date code of 0812 was made in the eighth week of 2012, or late February of that year.) There is sometimes other info on a tire depending on the brand and model, such as “WW” indicating the tires are white-walls, or “TL” indicating the tire is tubeless.
The date code shown here, “1411,” means “Week 14 of 2011.”
Bias-Ply or Radial Tires?
This has to do with the construction of the tire, which affects its resultant ride and handling characteristics. Generally speaking however, bias-ply tires last longer and ride “softer” at the expense of reduced grip, and radials are stiffer and provide more traction but don’t quite last as long.
There is no absolute rule for which you should choose, as it depends on your bike and what the manufacturer recommends. Some OEMs use bias-ply tires and some even mix bias-ply and radials; the rule of thumb when mixing is to only use a bias-ply in front and a radial in back, and not the other way around.
They say money can’t buy happiness. But it can buy you new tires, and they’ll make you pretty happy.
Helpful Tips for New Tires
- Inflation is crucial. No, not the inflation that makes your money worth less each year. This is the good kind of inflation – maintaining the proper tire pressure in your tires consistently. Even slightly over- or under-inflating your tires can have a significant negative impact on load, handing, and tire wear.
- When in doubt, go OEM. A best practice is to replace tires with exactly the same size as the ones that came as OEM equipment. But if you feel confident, it may not hurt to experiment with slight differences in size and style. Sport bike and dirt/dual-sport riders do this frequently.
- Keep weight off tires when its sitting. If you don’t ride daily (and most of us don’t) it’s good idea to keep your bike on stands to take weight off the tires and prevent flat-spotting. If you don’t have a stand, try rolling it forward or backward a few inches once in a while.
- Raise tire pressure with a passenger. It is recommended to bump tire pressure up a little when carrying a passenger; usually 1-2psi in the front, and 2-3psi in the rear.
- Break them in gently. Break in your tires by riding at an easy pace for about 100 DRY miles (wet miles do not count.) Vary the route to include curves in both directions to break in the sides as well.
- And for goodness sake…don’t ever put tire shine on motorcycle tires!
Motorcycle tire delivery sure has changed a lot over the years. They ship faster than this now!