Under Pressure

As we all know motorcycle tires are expenses.  Getting the longest life out on them is a difficult task.  One of the factors involved in getting the longest life out of them is maintaining proper air pressures.   When maintaining air pressure our tires will last their longest and give us what our hard-earned money was meant to.

Determining proper tire pressures is not as hard as it seems.  First, we will need some tools.  The obvious tools a tire pressure gauge the not so obvious tool is a method of determining proper tire pressure.  Some of my colleagues and I when we were younger have an opportunity to capture some experience in this.  We were intrigued and curious with what the proper tire pressure might be full of the race bikes we were running.  After some experimentation with tire pressures at the racetrack and some questions to the tire manufacturers we came up with the following method.

Tire pressures can vary for many reasons.  On motorcycles, front to rear tire pressures can vary.  The weight of the rider can make tire pressures vary.  The riding style of the rider can vary tire pressures, and finally speeds.  The higher the speed the higher the pressure due to increased friction causing heat causing air to expand resulting in higher pressures.  Riding styles vary tire pressures for the obvious reason.  There are many different writing styles.  Breaking abilities, tire sliding, aggressiveness, these are some examples of differences in riding styles that can vary tire pressures.

So with all these variances,  a method of determining the correct tire pressure is to measure the pressure after of riding for an hour or so.  This period of time will help determine the correct rise in pressure for your riding style and your motorcycle and its weight.  By starting with a cold tire pressure and measuring after an hour of riding.  You will be able to determine the differences between these two pressures.  You will be looking for a change of 10% on the front and 20% on the rear in the tire pressures.  Examples a tire that runs 32 psi cold will have a pressure of 35 psi when warm on the front of the motorcycle and 37 to 38 psi on the rear the motorcycle.

To understand this better try to imagine, what is called the contact patch of the tire and how large it is with more or less pressure.  The smaller the contact patch, the less heat is generated resulting in the smaller rise of tire pressure, and the opposite for the larger contact patch.  The smaller contact patch being a factor of too much air in the tire.  The larger contact patch being a result of too little air in the tire.

If you are concerned with your tire wear your safety your tire and expenses, try this method of checking tire pressures for increased tire life safety and decrease in tire expenses.

Here's hoping to give you a wave from the oncoming Lane.

Ross