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Several weeks ago I wanted to increase the air pressure in my tires to max sidewall pressure. I drove to four local gas stations before I finally found one with an air pump that (a) worked and (b) didn't take forever to increase the air pressure.

What other options do I have to pressurize my tires at home? Will a bicycle tire pump work? Are there at-home air pumps available?

Bike pumps work fine, but you can get pumps that plug into the cigarette lighter/12V power supply that have pressure gauges built in.

Kirk

Bike tires can be pressurized to 100psi or more. One will work on your car, but it takes a lot of pumping. A car tire is much bigger than a bike tire, more volume to fill and pressurize.

I have a little yellow box that is used for emergency jump of the battery (a gift) It also includes an air pump for tires. It works and is pretty cheap, but limited to running 10 min, then you must let it cool down. A home air compressor works really well, but that is talking more money and the existance of storage for it, ect.

Several weeks ago I wanted to increase the air pressure in my tires to max sidewall pressure. I drove to four local gas stations before I finally found one with an air pump that (a) worked and (b) didn't take forever to increase the air pressure.

What other options do I have to pressurize my tires at home? Will a bicycle tire pump work? Are there at-home air pumps available?

I use the Interdynamics 120V power compressor ($40 + s/h) from Amazon. Usually takes me 2 minutes or less to bring each tire to sidewall max PSI. Here's the link to product on Amazon.

http://www.amazon.com/gp/product/B0007ZAJC2

I bought a nice craftsman air compressor/storage tank for about $130. It takes me about 5 seconds to fill each tire now ;).

Several weeks ago I wanted to increase the air pressure in my tires to max sidewall pressure. I drove to four local gas stations before I finally found one with an air pump that (a) worked and (b) didn't take forever to increase the air pressure.

What other options do I have to pressurize my tires at home? Will a bicycle tire pump work? Are there at-home air pumps available?

I had the same problem. Service stations just don't provide much "service" any more. :( I went to Lowe's and bought a small air compressor with a gauge. It cost about $45 and works great. Now I keep the bikes, scooters, and the car tires pumped up to the max sidewall with no problems.:)

If you want to go about your max sidewall you'll need more than the typical cigarette lighter pump. I've burned out a couple trying to get above 65psi.
I'm saving up for an 120psi air compressor.

I personally witnessed a hand pump outperform an electric pump this weekend.

I thought I better include evidence.
http://www.cleanmpg.com/photos/data/591/hi_psi.JPG

And that very hand pump was thrown together out of trash-picked
parts, so was essentially free.
.
_H*

if you have really good lungs you might try blowing them up....

Personally I use a bicycle pump mostly because I ride my bikes a lot. I keep one in my car for when I go mt. biking on trails, and one in the house for road bike rides. They'll easily give you 150psi. Granted it'll take a little bit of effort, but jus think of it as your exercise for the day. Also, once your tires are inflated, kepping them there only requires a couple of pumps on colder days.

if you have really good lungs you might try blowing them up....

Personally I use a bicycle pump mostly because I ride my bikes a lot. I keep one in my car for when I go mt. biking on trails, and one in the house for road bike rides. They'll easily give you 150psi. Granted it'll take a little bit of effort, but jus think of it as your exercise for the day. Also, once your tires are inflated, kepping them there only requires a couple of pumps on colder days.

Luckily there is free air service at a station near work. And I usually get my exercise trying to start my old leaf blower.

I personally witnessed a hand pump outperform an electric pump this weekend.

So what's your definition of outperform? I've been looking to replace my old Black & Decker Air Station, but I'm not convinced that I could manually pump the FEH tires like I do for the Trek. So, what was Hobbit's PPP (pumps per psi) in the picture? That is Hobbit, right?

Thanks,
- Rob

i had a flat tire, and even with a hole in the tire, i managed to pump it up to 35 psi in about 5-10 mins. tiring, but doable. iactually prefer bike pumps. if ur looking to lower ur carbon footprint, the energy for the compressor comes from somewhere! lol, bike pumps r like $10, save money, and electricity!

I bought this one:

http://www.amazon.com/Slime-COMP06-Power-Heavy-Duty-Inflator/dp/B000M8R0QM/ref=pd_bbs_sr_3?ie=UTF8&s=automotive&qid=1214438450&sr=8-3

a while ago because I needed something that could inflate the tires of our Suburban up to 70-80 PSI (as recommended on the door sill sticker for towing). It's performed wonderfully so far, but I can't vouch for its long term durability except to say that it's advertised as being heavy duty and being for truck and SUV tires so it should be able to take plenty of pressure (no burning out above 65 psi).

Only caveat is that while it's a 12 volt cigarette lighter compressor, it requires something like 15 amps. That's above the rated capacity of the lighter in my Civic and my gf's Volvo and right at the rated capacity of the Suburban. This means NO powering it with the alternator with the engine on. Since I'm not really keen on letting the compressor drain the car's battery I just use it with my emergency jump starter battery which has a lighter plug on it. That small battery has enough juice to run it for about a half hour, which is longer than the unit's duty cycle between cool-off times anyway.

The vintage leather belted single stage compressor maxxed out at about 77psi. The Hobpressor could go 80+!!!

The vintage leather belted single stage compressor maxxed out at about 77psi. The Hobpressor could go 80+!!!

80+ :eek: He must be hiding some awesome muscles under that shirt! :D I'll have to give it a try.

My cheap electric compressor can go way over 100PSI. I know because I pump up my cannon with it :flag:

BTW, it still takes forever though. It took me about a minute to increase the pressure in my Jeeps tires from 37-40PSI.

I have an electric that plugs into the cigarette lighter... It's supposedly good for 300 psi, but I'll never see that, since it takes about 5 minutes to get from 30psi to 40psi. Lesson learned? - Get a pump with a high flow rate.

The cross-sectional area of the piston in the "hobpump" is probably
a little less than a square inch. So if I can push down on the
handle with, at a wild-ass guess, 60 or 70 pounds, that's enough
to push 80 PSI out the hose. Then it becomes a problem of
VOLUME, i.e. I have to push enough air up the gradient between
ambient and whatever's in the tire to move that air into the
tire. So here's a really basic physics lesson. I can produce
enough FORCE across a unit of AREA to overcome the existing
pressure in the tire and move more air into the high pressure
area. Now, I have to exert that force over a DISTANCE, i.e.
about half the stroke of the pump handle -- the first half
doesn't really count since it's building pressure in the pump
cylinder, and the air doesn't start really moving until the
bottom half. [And the piston in this thing is a little flakey.]
Still, that's FORCE over a DISTANCE which represents WORK. It
takes a certain amount of WORK to bring the tire up to 80 PSI,
obviously -- the number of pump strokes needed. Now, how *fast* I
perform that work is WORK per unit TIME, aka POWER. If I could move
the pump handle at a blur and push all that air over the pressure
gradient in a few seconds, then you'd want to wonder what I'm hiding
under that shirt. But I don't. I pump at a normal rate, taking a
couple of minutes per tire [remember, these are still fairly small
tires esp. on the Insight] and while it's a bit of effort, it's
nothing a human isn't capable of. And the bottom of the pump
definitely gets a bit warm, as some of the energy is lost through
that path as well.
.
Many of these same principles apply to piston engines...
.
One problem the electric compressors have is very tiny cylinders,
so even though they reciprocate very fast they actually don't move
a whole lot of volume per unit time. Frankly, it takes about the
same time for a given pressure rise with an electric compressor or
the hand pump, simply because you can't draw as much POWER [in
this case, volts * amps] from the 12V cig-lighter outlet. Let's give
a conservative estimate that I'm pumping at a rate of about 120
watts -- if I really went at it with all my effort, I might make 200,
but I'm trying to be a little relaxed about it and save my sweating
for inside the car when I'm out on a run. 120 watts pulled from a
12V outlet is, guess what, 10 amps. Most of these power outlets are
fused at 15 A, with the expectation that you won't really pull
anywhere near that.
.
What you really don't want to think about is all the ENERGY stored
in the tire, i.e. pressure * volume, and what you'd hear if it
was abruptly released.
.
_H*

... I can produce enough FORCE across a unit of AREA to overcome the existing pressure in the tire and move more air into the high pressure area. Now, I have to exert that force over a DISTANCE, i.e. about half the stroke of the pump handle -- the first half doesn't really count since it's building pressure in the pump cylinder, and the air doesn't start really moving until the bottom half. [And the piston in this thing is a little flakey.] Still, that's FORCE over a DISTANCE which represents WORK. It takes a certain amount of WORK to bring the tire up to 80 PSI, obviously -- the number of pump strokes needed. Now, how *fast* I perform that work is WORK per unit TIME, aka POWER. If I could move the pump handle at a blur and push all that air over the pressure gradient in a few seconds, then you'd want to wonder what I'm hiding under that shirt. But I don't. I pump at a normal rate, taking a couple of minutes per tire [remember, these are still fairly small tires esp. on the Insight] and while it's a bit of effort, it's nothing a human isn't capable of.

So, if my lesser physics mind :confused: can grasp this ... My larger tires can be done this way, but it will take me longer to go from 77 to 80 because I'm pushing through more space to get to the high pressure area? And the volume not being linear, I could expect 8-10 minutes per tire instead of a couple of minutes? It sounds like a good work out to me :D

So this may sound strange (remember, lesser physics mind), but if I the roll the tire so that the valve is higher (above the wheel instead of below it) will that reduce my pumping time?

Blinding me with Science is gooooood.
- Rob

The FEH at the Championship took MUCH longer to pump up than the Insights did. Larger tire = more air required to reach the same pressure.

Rolling the tire will make little difference. Once the air has traveled through the constant-length hose, it's in the tire, and pressure equalized through the tire immediately.

So I am out in my driveway last night hand pumping my tires up to 44 psi with a bicycle pump and my wife comes out and says "what on earth are you doing?" Thought I was crazy. Nice roll on the downhills this morning, though.

There is one more way to inflate tires. That is with a nitrogen, N2, tank. Most AC service people carry nitrogen on their truck for troubleshooting system leaks.

You can buy a small HP tank used with a new valve and regulator for ~$200 at a welding supply house. Add a short hose and an air check from Home Depot and you have your own tire inflating station. Refills on the tank are about $15.

Clean, dry nitrogen is by far the preferred method. Gas station air will have water, sometimes oil, and sometimes particulate matter in it.

Of course, if you're traveling or have an emergency then gas station air is the only way to go.

Note: the gas station tire gauge and pencil type gauges are notoriously inaccurate. Get a good digital tire gauge in a case.

Faithful and True.

There is one more way to inflate tires. That is with a nitrogen, N2, tank. Most AC service people carry nitrogen on their truck for troubleshooting system leaks.

You can buy a small HP tank used with a new valve and regulator for ~$200 at a welding supply house. Add a short hose and an air check from Home Depot and you have your own tire inflating station. Refills on the tank are about $15.

Clean, dry nitrogen is by far the preferred method. Gas station air will have water, sometimes oil, and sometimes particulate matter in it.

Of course, if you're traveling or have an emergency then gas station air is the only way to go.

Note: the gas station tire gauge and pencil type gauges are notoriously inaccurate. Get a good digital tire gauge in a case.

Faithful and True.

Get a paintball compressed air cylinder....plenty of pressure. I gots one that will hold 90cubic inches of air at 4500psi...

slap a regulator on that bad larry and you'll be fillin tires left and right.