4 ms·

Have done this, can confirm, it does take a while :) like tricept workout kind of while, but it does work... (for expediency I used a floor pump serfas or somet

• jandrese 7y ago
  I had to do this once myself. I was surprised by how hot the bike pump was by the end. It was on the threshold between warm and hot. It wouldn't burn you on contact, but you wouldn't want to grip it hard for more than a couple of seconds either.
  • schoen 7y ago
    Was that more due to gas thermodynamics or mechanical friction? I use bike pumps a lot, but only on bikes, so I've never experienced this.
    • jandrese 7y ago
      I assume it was mostly due to ideal gas law reasons. Pumping up a highish pressure truck tire (~65 psi IIRC) did take quite a long time and I was pretty exhausted by the end.
    • mikestew 7y ago
      Compress a gas, it warms up. I imagine that's the large part of it. Go grab the cooling fins on a large electrically-driven compressor after it's been running a while. No, wait, don't do that if you like your fingerprints. The cooling fins aren't to cool the motor, they're to cool the compressor housing where the piston goes up and down to compress air.