The complete guide to choosing motorcycle tyres: understand how speed codes work and what the abbreviations on the shoulder of the tyres mean.
Choosing the right tyre for your bike is never easy. There is a wide range of commercial offers, many prices at stake and possible discounts. But with our advice, you can easily make the right choice of tyre for your motorcycle or scooter.
How it is made
The tyre, going from the inside out, consists of the following elements: the carcass (also called carcass ply or belt), the carcass ply (consisting of a very strong ply whose function is to give the tyre the desired shape and to take all deformation and loads), the tread (responsible for the traction property of the motorcycle and the discharge of water, sand and other pollution) and the sidewalls (which are the thinnest element, characterized by great resistance to deformation). The tyre can have two types of structure: traditional or diagonal (the wires of the ply are placed at less than right angles to the tread line), belted (with a layer of reinforced ply and characterized in the marking by the letter B) and radial (the cables on the plies are arranged radially and cross the rubber from side to side. This structure offers advantages in terms of stability when cornering and at high speeds).
First of all, you must keep an eye on the measurements, i.e. the information in the vehicle registration book and which you must follow. The first number indicates the width of the tyre in millimetres. The one after the bar indicates the percentage ratio between tyre height and width. “R” indicates that it is a radial tyre. “ZR” indicates a radial tyre that can withstand a speed in excess of 240 km/h. This is the diameter in inches of the rim on which the tyre can be fitted.
Load and speed
After the abbreviation M/C (i.e.: rubber dedicated to motorcycles) there are other very important sizes: the number indicates the load index (the maximum weight that the tyre is able to support, ranging from 40, i.e. 136 kg, up to 83, i.e. 487 kg), the letter the maximum speed code supported by the rubber (which can range from a minimum of A to Z, i.e. over 240 km/h, W or 270 km/h and Y, i.e. 300 km/h). The load index and speed code must not be lower than those indicated in the motorcycle’s registration book.
No letter – traditional tyre
B – belted tyre
R – radial tyre
TT -pneumatic with inner tube
TL – tubeless tyre
M/C – tyre intended exclusively for motorcycles
A – tyre in special version
NHS – not for motorway use (tyres produced exclusively for racing use on the track as they are not officially homologated)
RF – reinforced tyre
Front – front tyre
M+S – (i.e. MS, M-S M&S) Tyre suitable for use in mud and weather conditions