What to Know About Tire Pressure for Electric Bikes

One of the greatest feelings in modern life is the ability to affirm for yourself, “I know what I’m doing and I know why I’m doing it.” So, why electric vehicles? Why are we interested in traveling on these new and unusual contraptions? Why do we do this?

It can’t just be the sense that we’re trying to fight back against global climate catastrophe, and it can’t just be that they’re new and interesting. It’s almost always a combination of factors: making your commute more fun and less strenuous, going on adventures in places you couldn’t otherwise get to. Whatever your reasons are, there are basic things you must learn in order to stay safe, and we at Ridepanda are here to equip you with the knowledge you need to not end up injured, or, even worse, someone with a cool bike stuck in the garage gathering dust.

Welcome to the first lesson of the Panda academy: Tire Pressure

Your tires are the part of your vehicle that make actual physical contact with the road you ride on. The traction they generate is what keeps you, the rider, cruising safely through space. Tires are also the first thing that might befuddle an inexperienced bicycle owner just on the cusp of starting to really enjoy their new, cool vehicle. 

Why do tires present such a hurdle? Because an ebike can’t be shipped with the tires fully inflated, and the bicycle can’t be safely ridden without the tires inflated to the correct pressure. So before you get started, you have to locate a bicycle pump (we sell those!), or a gas station with an air and water station (ack!), or a nearby mechanic shop with an air compressor you can use.

For some, the option of a portable air compressor, about the size and shape of a typical power drill, might also work. Those can be found at big box hardware stores or online sometimes. Whatever method you use to get the air in your tires, you have no hope of having safe electric vehicle fun without properly inflated tires.

Once you decide on a method for getting the air in your tires, you’ll have to find out how much air to put in them. A solid piece of advice is, don’t rely on your own intuition. It’s often written on the side of your tire. It’ll be a value like “30 PSI” or a helpfully complete sentence like “Inflate To 30 PSI,” and these values are determined by many hours of engineering and stress testing.

filling-tire-pressure-on-ebike

PSI is an abbreviation of ‘pounds of pressure per square inch,” a scalar measurement that describes not only the volume of air in the tire, but how forcefully the air is pushing out against the tire, yearning to be free. But instead you keep that air captive, and it helps you ride safely, ensuring that you are the one experiencing feelings of elation and freedom.

The part of your tire that is, at any time, touching the road is called your “contact patch.” The shape and size of your contact patch is determined by the the shape of the tire and how much air pressure is in it. Too little pressure, and your contact patch is too big. You end up with much greater “rolling resistance,” the term for the effect of the road friction fighting back against your forward motion. Too much rolling resistance, and you could actually damage your electric motor. Your motor is only designed to fight the road so much.

electric-bike-tire-up-close-to-see-traction

If you overinflate your tires, your tires will be too rigid, and your contact patch will be too small, which results in too little contact with the road, which means you run the risk of a catastrophic loss of traction, which is likely to result in injury.

Other things can hurt your traction too. Pools of liquid, clumps of dry leaves, oily substances. Luckily, the same engineers and designers who determined the appropriate pressure in your tire, also put a lot of thought into the construction of the material your tires are made of, as well as the shape of your treads. You’ve got engineers and experts on your team, and all they ask of you is to keep your tires properly pumped up.

Lastly, we’ve got to talk about how often to pump your tires up. The short answer is, every ten days to two weeks is ideal. Air escapes your tires slowly by pushing through the rubber in your tubes and tires, which are slightly porous. They deflate when your vehicle is just sitting in your garage, they deflate when your vehicle is being used (but not that much more than when they sit in the garage, generally.) Checking your tire pressure is also a strange endeavor. Every time you check it, you change it. Checking it lets a little out. Strange, huh?

Does this mean that the right approach is to add slightly more pressure than is recommended in order to compensate for the one or two PSI you’re going to lose? Our answer to that is at the heart of enjoying electric vehicles generally: don’t overthink it. Be safe, be aware of the basics of bicycling, keep those tires pumped up, and have fun!