How to pump your Tyre with a computer!

[abdullahseba]

Anyone ever done this? 
We don't have car and the 12v PSU I use-to use for powering the pump was a cingwish one with bad overload protection that it powered the pump... until it stopped working.
So when I needed to pump my Tyre I tried a good 12v 4A PSU. But no good the overload kicked in so I tried a another 12v 5A... still no good.
I didn't have anything higher so after a good think I tried it on one of my 15-20 odd computers (lost count you see ) and it worked on 5v but it was to slow. Perfect on 12v.

[electr_peter]

Interesting use of PC's PSU, that for sure

How much power/current does that air pump require? If 5A was too low, would 10A or more be enough? ~10A at 12V makes it >120W item - I expected much less power is needed (I tend to use hand pump for bike tyres).

[abdullahseba]

Interesting use of PC's PSU, that for sure

How much power/current does that air pump require? If 5A was too low, would 10A or more be enough? ~10A at 12V makes it >120W item - I expected much less power is needed (I tend to use hand pump for bike tyres).

I am not sure how much it draws. I broke my hand pump when I was younger by turning the bicycle pedal upside down and sticking the pump through the wheel spokes which broke the pump    

[hexreader]

Went through exactly the same exercise about 3 months ago. 5A current limited bench supply only managed about 8Volts at 5A which got the bike tyre partially inflated, but pump gave up well before the required pressure.

Computer PSU worked perfectly (with the green wire shorted to 0V black wire), but I have not measured the current draw.

[128er]

Thumbs up for that hack. Have to do the same for my metallurgical microscope. It has a 100W/12V lightbulb. My dual output benchtop PSU was not capable of that. Now my old Pentium 4 machine stands right next to the microscope, only for this purpose. 

[McBryce]

What OS did you use. 

McBryce.

[AndyC_772]

I've tried to power a car tyre pump with a 12V SMPS, like a laptop supply.

It didn't work; although the mean current draw was well within spec (about 10A IIRC), the pump draws a pulsed load with peaks which the SMPS couldn't manage.

Best stick to using a car battery, IMHO.

[jh15]

so if you get a flat 20 miles from home, you have no pump in your bike bag?

[TerraHertz]

You can make a short adapter hose from a car tyre valve to a bicycle valve (usually the same.)
Then you have an air source where ever there are parked cars. 

[abdullahseba]

What OS did you use. 

McBryce.

LOL bicycles7