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What if the air is let out of car tires?

Someone let the air out of my BICYCLE tires while it was locked outside. No big deal, I just used my bike pump to fill them back up.

But this got me thinking: What I would do if someone let the air out of my CAR tires? I have only one spare tire. I don’t have comprehensive coverage or Triple A.

Can a bicycle pump inflate a car tire with enough air to get to a gas station? Or would the bike pump be a futile attempt on car tires (35 psi)?
Would I call around to locate a repair truck with an air compressor?

It can, but only if you’ve been doing your reps every morning!
The problem is that a bicycle pump isn’t designed to move enough air to fill a car tire. It’ll handle the 35psi pressure with no problem, but by the time you pump enough air to fill four car tires you’ll be in the ER having your rotator cuff operated on.

There are, however, 12VDC air pumps specifically designed to fill car tires available just about everywhere for about $15. They plug into a cigarette lighter or power port.

Be careful riding that bike for a while. deflating bike tires often results in the tube wrinking and when re-inflated a wrinkle can become a pinch point that bursts. It helps to powder tubes whenever they are deflated. Baby powder works fine.

For the unlikely event, just get one of those 12v compressors as mentioned or call a service truck. Both will take about the same time and about the same cost. Everyone though should have a regular compressor at home like flashlights and power drills. I’ve got several.

If you deflate your car tires for some weird reason, you may not be able to reflate them if the seal around the rim is broken. Car tires DO NO HAVE TUBES!!!

I have one of those air pumps and even with it, it takes some time to add air say from 30 to 35 lbs. Your idea makes very little sense, but this panel does provide answers.

You can also kill two birds with one stone by getting a power pack for jump starting your car in case of a dead battery, with a built-in tire inflator. I have one and use it frequently to top up air in my car and snowblower tires. The nice thing about this is you don’t need a 12v outlet nearby.

Using hand or foot-operated air pump would be exhausting if you needed to fill all four tires. A 12 volt compressor would be a lifesaver in such circumstances, as long as the tire seals are still intact and you’re in no hurry.

If someone let the air out of all four tires, one of those $15 12V compressors will not fill all the tires in a timely manner. They are only designed to top off one or two tires. There are 12V compressors that can fill all four tires pretty quickly but they cost about $60.

If the tires were deflated in place, I don’t think they will unseat the bead so re inflating them should not be a problem. You can inflate them with a small low cost 12V air pump, but you need to know the duty cycle of the pump. That is the run time to the cooling off time. Some will run for a total of 6 to 10 minutes in a 30 minute period. If it is run too long, it gets too hot and will melt some of the plastic internal parts.

You should carry some type of 12V air pump in your vehicle just for emergencies anyway, even if it is one of the cheaper ones. In an emergency, you might not need to pump the tires all the way up to the recommended pressure. You could put in 15 psi and drive a short distance (up to 3 miles) at low speed (<35 mph) to a shop and have them filled up there.

If enough air is let out and the bead between the tire and the rim separates, you will need more then a bike sir pump. You will need a good shot of compressed air. Let’s hope they don’t remove the valves which is even worse.

Most folks, if they found all their tires flat, would just call a tow truck. The tow truck often has an air compressor and could re-inflate them on the spot; if not, they’d just tow the car to a shop. If you have “comprehensive” coverage with your auto insurance policy, it might well cover that situation, so there would be no charge to you.

Another consideration, If all four tires were flat, me, I’d suspect a prank and that the valve stem inserts were removed too. In that case it wouldn’t matter if you had a compressor or not.

fyi, there’s a “big tank of compressed air” product available you can buy to re-inflate car tires even if the bead has been broken. Delivers a big volume all at once. Used by the 4x4 off-road community.

"If not, they’d just tow the car to the shop"
Hopefully not. ;=()

I inflated a flat tire on a van once using only a small bicycle hand pump. It was tiring (very tiring), but it worked. Fortunately the bead was already seated.

I wonder who would go through the trouble of deflating all four tires of a car using the valve stems instead of slashing the tires. Why would anyone interested in deflating your tires go through that much trouble? Has Robert Gift created a new user name?

I have pumped up car tires with a bicycle pump. It takes about 15 minutes per tire if the bead is seated. I routinely use a bicycle pump to maintain pressure in my car tires. It doesn’t take too long to take a tire from 28 psi to 32 psi. It’s nice if the tire pump has a pressure gauge so you know when to stop.

I would not want to try a bicycle pump to go from flat to inflated. I use mine, but only to go from say 29 to 32 psi. And that’s a decent amount of exercise.