I hopped in the car this evening to take my kid to gymnastics team practice only to see the tire pressure indicator on the dashboard. I ran around the car quickly to make sure nothing looked obviously bad or worse relative to the rest of the tires, and jumped back in because of the time. After dropping off the tween at the gym I drove around to 4 Wawas (they have free-to-use air pumps) but struck out at each because of either broken pumps or long lines of cars. I headed home in frustration, hoping I could sort this out with the barely-powerful-enough battery pump I had at the house.
It took well over 5 minutes to get my front driver’s side tire from 24 to 30 PSI (all 4 of my tires have a recommended cold inflation pressure of 30 PSI), then the battery indicated it was low. Not great, Bob! So I charged it while I ate dinner, hoping I had enough time to inflate/charge/repeat on the other 3 before returning to the gym for pickup. But then!
I have a rather specialized floor pump for my bikes: the Topeak “JoeBlow Sport 2Stage”. This pump can operate like most floor pumps at high pressure or, with a flick of a lever, use twin air chambers to deliver nearly triple the volume of air per stroke up to around 30 PSI. This is super useful for low-pressure gravel and mountain bike tires set up to tubeless, like my main bike. But 30 PSI? High volume? Car?
I took the battery pump outside again along with the floor pump and set up the battery dude on the front passenger tire. It also needed to go from 24 to 30 PSI, so I let it run while I hooked up the floor pump to the rear driver’s side tire. The dial read around 22-24. Well, reader, I got that tire up to 30 PSI in about 2 minutes while the battery pump was still whirring. So I took it off and finished up (along with the rear passenger tire) with the floor pump!
Would I want to use a hand pump all the time? Nope! But it sure is nice to know that a modern, high-volume bicycle pump is plenty capable of making up a 20% pressure deficit in my car tires.