Motorcycle Tires – Learn to Read your Tire Codes

It is safe to say that motorcycle tires are the parts of your vehicle that you overlook the most. We can easily explain this phenomenon since they are not in plain sight while riding and you can travel on the same tires for thousands of miles. All you need to do, from time to time, apart from the occasional misadventure, is to check inflation in them. That being the case, they indeed are an integral part of your ride. Whether you realize it or not, companies spend hundreds of thousands of dollars in research and development annually.

Read on and learn everything you need to know about your motorcycle tires. As a bonus, I will also teach you how to read the information and codes imprinted on the sides of the tires, and I’ll let you in on some awesome accessories I have discovered recently.

Motorcycle Tires – An Introduction

First of all, let’s start by stating some cold facts about motorcycle tires you might not be aware of. Let’s dig right into it:

The history of motorcycle tires

Tires were first known as the “pneumatic tire” (British English spelling). They were invented by John Boyd back in 1888 and were first used on a motorcycle in 1897.

At first, they all used inflatable tubes inside the outer tire which was attached to rims made of steel and wood. The roads weren’t all that great back then, so as you can imagine this set up wasn’t such a great combination. Riders were plagued by constant ‘flats’ until the 1970s when the first tubeless motorcycle tires started appearing on the market. These types of motorcycle tires were made possible with the advent of alloy wheels.

Many technological developments separate the tires of today from the ones used in the 19th Century, but the principle remains the same. They are still basically rubber tubes inflated with air to enable our motorcycles to travel more graciously and comfortably along the highways.

Motorcycle tire construction

Motorcycle tires are not just pieces of rubber in the shape of tubes that sets in your bike wheels. Nowadays they have become an increasingly complex system of layers. There are a number of stages that most motorcycle tires pass through and only the final component is what we call ‘rubber.’ The product is entirely different from that used in the nineteenth century. The composite used by most major brands today is a mixture of petroleum, acids, chemicals, silicone and carbon black. This composition is what constitutes the outer layer of the modern motorcycle tire. It is the final layer because it utilises the rest of the layers as a mould to support its shape. The final stage in the whole process is to use heat to vulcanise the entire composition into one single unit.

Belted (B) or Radial (R) Motorcycle tires?

It is the first parting of the ways related to tire construction. The choice between belted and radial tires determines the speed that the motorcycle tire can sustain. It is not just something you can choose like purple, yellow, blue or black for the colour of your gas tank. While it is true that chronologically, the time period of their invention is different, they are both in commercial use today. Let´s take a look at the main differences:

Belted – Also known as Bias Ply motorcycle tires, have plies or layers in a criss-cross pattern. The materials can vary, but the design has been around for over a century. They have an amazing cushioning effect over Radials, and people prefer these tires for heavy loads. On the other hand, they retain more heat and offer less control at high speeds.

Radial – Radial motorcycle tires are more modern in design. The carcass is durable and traverse the entire tire and run perpendicular to each other, and also displays a criss-cross pattern among each other. These materials can be steel, Kevlar or polyester. Radial motorcycle tires are much stiffer than belted tires and perform better at higher speeds, but this also has a disadvantage in that it makes for a firmer ride too. Radials are the go-to tire for most manufacturers in the world as they are more durable because the materials inside the treads last longer. They are what you would most likely find in a modern-day, brand-new bike.

Motorcycle tire types

Well, we first divided motorcycle tires into two categories. But now we are about to split it even further, into multiple directions; not so much a roundabout, as a multi-exit deviation. We require different categories of tires depending on how we will use them. For example, the performance we expect for an off-road trip is not the same as that for a high-speed course or even for urban riding. Each environment has different demands.

Sports street

This is, perhaps, the most common of all the tires. Aggressive city riders, who like taking corners fast in any climate, love these tires. They are not very durable but are very versatile. This kind of motorcycle tire usually has excellent traction and stability.

Touring

These are the most durable of motorcycle tires as harder rubber defines its material which has pros and cons. On the one hand, these tires can handle cold weather better than sports tires; on the other hand, they have less grip and tend to handle poorly at higher temperatures.

Track

Normally racing motorbikes use these tires. They have a triangular profile that gives you more stability when leaning on one side. They are for performance bikes and not for everyday use. There is smooth tread on these tires, and therefore they have minimal grip especially in wet weather.

Off-road

Although they don´t provide much stability on paved roads, their knobby structure provides optimum grip on dirt tracks. Along with track tires, this is another of the specialised motorcycle tires. These tires can be dangerous if used for regular urban riding.

Understanding motorcycle tire codes

Besides the basics like the rim diameter (otherwise it won´t fit your bike), there is much more information written on the sidewall of a motorbike tire. Let´s take a look at the essential four pieces of information you have to know.

You might be thinking right now that you always use the same brand and model of tire, and so maybe knowing the different codes that tire manufacturers use is not that important. You could rely on the employee’s attire shops to know their stuff and do their jobs right. But, what if you knew better than them? Knowledge of this kind might save you from a tough situation; knowledge is freedom, and learning about motorcycle tires is a rider’s freedom.

Direction of rotation

This is the simplest of all the indicators. You will notice that your tire has an arrow. Well, that is exactly the direction that guides you to turn when going forward.

Load and speed index

This is another straightforward indicator made up of a two-digit number and a letter. You will read something like 58W, which indicates that not only do you have a set of tires that can reach 270 km/h but also that they can transport up to 520 pounds (236kg) in weight. There are charts for this available in Wikipedia if you want to know the letters, speed limits and loads.

Tube designation

This is, perhaps, the second easiest indicator to read. For example, you might see something like: “Tubeless, tread: 4 plies nylon, sidewall: 2 plies nylon.” What does it all mean? Well, it is relatively easy to decipher: It says that you have a tubeless tire that has four plies of nylon on the tread and two plies of nylon on the sidewalls. This is very helpful to determine the resistance, durability and stiffness of your current tire.

Summary

The summary usually condenses all the information you can find somewhere on the tire. Let’s break it down:

• Tire width – This number indicates the width of your tire in millimetres measured from the widest point on each side.
• Aspect ratio – They calculate your tire´s aspect ratio using the height of the sidewall and the tire’s total width and then express it as a percentage.
• Speed rating – You can go for the chart available online to find these ratings. This is important for those riders who make improvements to their bikes, and it enables them to check whether they need a higher category of tire for their bike. Also, if you are riding an older model and can´t find the exact replacement for the originals, you can take a look at this chart.
• Tire construction – In the “tires construction” section you will find a very clear explanation of what the letters refer to (90% of the time you will most likely see the letter R).
• Rim diameter – There is not much to explain. In this section since you must know this information before buying your tire. Purchasing the wrong rim diameter will be an epic fail since you will not be able to fit it to your bike. Again, for those who change their bikes from stock, bear in mind that sometimes, replacing the front fork, for example, can change the rim diameter you need.

Understanding these codes is undoubtedly beneficial in the long run. There is no way you can remember all the charts, but having them handy is an option. Remember that knowing what you are talking about might save you from a scam.

Conclusion

Motorcycle tires have closely followed and complemented the improvements made in terms of vehicle speed and power over the years. The major motorcycle tire companies ensure to make faster rides safer, and that’s the reason there is a boost in the ongoing development of engine power. On the contrary, they were there, pushing the limits of innovation time after time. As a result, motorcycle tires are now the safest they have ever been. Besides safety, they now also incorporate many specialised measures that improve speed, grip and suspension.

All technology and funding applied by these companies towards improvement, research, development and manufacture have paid off. Motorcycle manufacturers expend many staff-hours finding the perfect tires to match their vehicles.

Now that you know all there is to know about these rubber saviours, you can make the most of your motorbike knowing that you will be safer at all times. Feel free to share this valuable information in riders´ forums or with friends and family. We would also love to hear your own experiences.

Happy riding!