How much do you think about the tires on your motorcycle? How about the correct level of tire inflation? If the answer is “not often,” you’ll want to reconsider. Let’s discuss why.
Motorcycle tires connect us to the road
Whether you’re accelerating, cornering, or braking, safe motorcycle riding relies on two small contact patches where the tires meet the road. Tires are among the most critical design elements on today’s almost maintenance-free motorcycles, delivering performance, service life, and fit beyond anything offered in the past. But your tires do require some attention before you head out on the road.
Tire performance is all about the pressure
The high standard of performance and value expected from modern motorcycle tires is the result of constant research and testing by tire manufacturers. But the performance depends almost entirely on your tire maintenance habits. The key is proper inflation, which you need to check before every ride.
Air always escapes
We’ve been filling our tires with air since the beginning of pneumatic tires. Here’s what air is composed of:
1% water vapor and other trace gases
Even though tires are designed to hold air under pressure, those gas molecules can pass through the rubber through a process known as osmosis. Since the air inside the tire is under more pressure than the outside atmospheric pressure, it helps push the small gas molecules through the tire’s membrane. Nitrogen molecules—which are larger than oxygen molecules—move more slowly out of the tire, which is why nitrogen has become a popular upgrade for inflating new tires. A tire can lose one to three percent of inflation pressure each month. That’s an important fact to be aware of because prolonged riding with underinflated tires can damage the tire and increase the rate of pressure loss.
Temperature changes impact tire inflation
Temperature has a powerful effect on motorcycle tire pressure. As temperatures rise, tire pressure goes up, while pressures fall with lower temperatures. In fact, every 10-degree change in air temperature causes a two percent change in inflation pressure. Combine any air volume loss and a temperature-induced pressure reduction, and you could have dangerously underinflated tires.
When to take tire pressure readings
The correct time to check your motorcycle tire pressure is when they’re cold—meaning the motorcycle hasn’t been ridden for at least three hours. Manufacturer inflation specifications are based on cold readings and take into account the pressure increase that happens as tires warm up on the road. Be sure to use a quality tire pressure gauge to make sure your motorcycle tires are properly inflated.
As seasons change from warmer weather to cooler weather and back again, your pre-ride cold readings will keep your tires at a proper operating pressure in every season.