FUNCTIONS OF A MOTORCYCLE TIRE
Today, the level of technology in tyres and motorcycles is extremely high. Riders often forget that the tyre is the only point of contact between the bike and the ground, and that it must perform multiple tasks including steering, carrying a load, absorbing road shock, rolling smoothly, transmitting mechanical inputs, and wearing evenly.
STEERING: The tyre must steer predictably, regardless of the road or weather conditions. The motorcycle’s trajectory depends on the directional stability of the tyre. The tyre should transmit steering inputs without drifting off the intended line. Every bike has a specific recommended inflation pressure for each wheel. Correctly adjusting pressure for both front and rear tyres helps ensure steering stability and precision.
LOAD CARRYING: The tyre supports the bike at a standstill and while in motion, but must also withstand considerable load transfers during acceleration and braking.
SHOCK ABSORBING: Tyres roll over obstacles and damp road shocks, ensuring the rider’s and passenger’s comfort as well as protecting the bike. The tyre’s greatest asset is its flexibility, particularly in a vertical plane. The elasticity of the air inside the tyre helps it to absorb shocks from obstacles and irregularities in the road. The correct pressure thus helps achieve a desirable level of comfort as well as accurate steering.
ROLLING EFFICIENCY: Tyres should roll smoothly with minimal rolling resistance for a feeling of control and with steady, progressive wear.
MECHANICAL GRIP: Tyres transmit the bike’s mechanical forces of horsepower and braking. The few square centimetres that constitute the contact patch can make all the difference in a bike’s performance.
WEARING: Tyres need to maintain a dependable level of performance throughout millions of revolutions. Tyre wear depends on many factors (load, speed, condition of the road, vehicle maintenance, riding style...) but especially the quality of the contact patch. Air pressure plays a major role, affecting:
• the size and shape of the contact patch,
• the distribution of the mechanical forces on various points of the tyre in contact with the road.
These six functions determine a tyre’s safety, comfort and economy. You expect them to be present throughout the lifespan of the tyre, but you must take certain precautions. The tyre needs air to perform and to last, so it’s necessary to check inflation pressure regularly. Every tyre loses air, molecule by molecule, because of rubber’s natural porosity. Accidental causes such as valve or rim damage often accelerate air loss, as will small cuts in the tyre tread or sidewall. Air pressure affects every aspect of the tyre: safety, economy and riding enjoyment. The wrong pressure can degrade performance in all areas.Routine pressure checks can prevent many worries.