Can a Bicycle Pump Inflate a Car Tire?

Desperate times call for desperate measures, and you may find yourself in a situation where you have to make due with less than ideal tools to meet your needs. For example, you get up in the morning and get ready to go to work, only to find that your car tire is so low you can’t even make it to a gas station to air it up. What can you do? You realize you have a bicycle pump in the garage for the kids’ bikes, but you aren’t sure if you can get the job done with a bicycle pump. The short answer is, this is entirely possible. But you may need to take a look at some instructions to do it properly.

Setting Up Your Car

The best thing to do anytime you’re going to air up a tire is to assure your car is on a clear, flat surface. If your driveway is at a slight angle, this isn’t too big of a problem, but if there’s enough air in the tire to roll it to the flat street, that’s a better way to do it. You’ll get a more accurate reading on the actual air pressure in the tire. This will also make it easier to balance the pump you’re using.

Once you’ve got the car where it needs to be with nothing in your way, you should remove the valve caps from your tire. However, because these are so small, they can be very easy to lose. You may want to have a small container or even a Ziplock bag to put them in while you work so they don’t roll away.

Do Your Homework

Okay, it’s not something you have to know every day, so you probably have to take a careful look. But in order to fill your tire properly, you have to know the recommended PSI – pounds per square inch of pressure. Generally, there are a few places you can look for this information. Typically, if it’s not worn off (and if it is, it’s probably time to replace the tires anyway), the information is written on the tire itself, on the rubber, much like the size of the tire.

Another location you might be able to find it is on the inside of your door, usually printed on a sticker. If you can’t find it there, or if it can’t be read, you can check your car’s manual. You’ll be able to find the manual online if you no longer have a physical copy. Be sure to read carefully, and if you’re getting the information from the tires, make sure you check both front and back, since some vehicles have a different tire and pressure requirement for the back tires.

Checking the Pressure

As a responsible driver, you should have a pressure gauge in the glove box of your vehicle so that you are always prepared, in case of trouble. It’s part of a ‘standard’ maintenance set you should carry with you everywhere you go. In order to determine how low your tire pressure is, you’ll first want to clean any dirt or grime from the valve and then follow these simple steps.

  1. Press the opening of the tire gauge to the top of the stem (valve). Push it firmly into the valve until the hiss of escaping air comes to a halt. Then, release.
  2. Most gauges have a slide reader that shoots out the bottom to show what the pressure is. Take a look at the mark that is closest to the end of the pressure gauge itself to determine the actually pressure.
  3. Determine how far below the recommended PSI your tire pressure is. If your tire is even 5 PSI below the recommended amount, you should fill it.

As a side note, while you’re correcting the air pressure on one of these tires, you should take the time to check them all, since being low on air isn’t always visible.

Preparing Your Pump

The basic idea of actually using the pump is simple enough, but there are a couple of things you need to confirm prior to actually airing up your tire. A bicycle pump is a vital part of any bicycle tool kit and can come with more than one type of valve end – a Schrader valve (also called an American valve) and a Presta valve are both quite common. Bicycle pumps with a Presta valve have a thin, threaded metal cylinder at the end. These won’t work for your car tire. You’ll need a Schrader valve, and many pumps with Presta valves also come with a Schrader valve, which have threading for a screw on cap and a small metal pin inside.

Filling the Tire

Attach the bicycle pump valve to the air valve on your tire. You’ll hear air escaping until it seals, and that’s normal. Then, with the valve in place, raise and lower the pump bar steadily. Stop frequently to measure your tire pressure, since you don’t want to overfill the tire. If you haven’t reached the optimum pressure level yet, reattach your bicycle pump and start again.

Keep in mind that bicycle pumps are much slower to fill your tire than a powered pump, so it could take some time. Still, you want to at least get without 5 PSI of the recommendation before you try to drive your car. When you’re done, replace the valve caps, screwing on tightly so they don’t come off.

Conclusion

While it’s not the ideal situation, you can improvise when you need to pump up your car tires using a bicycle pump. The important things are to remember the type of valve you need on your pump, to measure the pressure so you don’t overfill or leave the tire too low, and to try to have a smooth, flat spot with nothing to interfere before you get started with the process. If you follow these instructions, you can easily – with a little labor to pump the air – fill a car tire with a bicycle pump.