It’s both surprising, and not, if you think about it. The way I’ve usually seen it happen is first the rear tire goes flat, then the front one. My theory is that both tires went through the same pile of glass/thorns/metal bits and they both picked up junk. the reason for the flat occurring on the back first is because there’s more weight on that tire, so the offending article works its way through the tread more quickly.
Modern bottom brackets use a sealed bearing type construction that keeps water and debris locked out, so they seldom go wrong. Maintenance is impossible so they need replacing when they do wear out. Older style cup bottom brackets need to be re-greased every now and again, and occasionally will need to have their bearings replaced. There are a lot more teeth on the chainring cogs than those on the rear cassette, so need changing less regularly. Cranks usually a solid one piece construction so there is not much to go wrong.
Unlike floor pumps, most hand pumps do not have pressure gauges. To get readings during my original round of testing for this guide, I built a special rig involving simple hardware-store parts. But the experts I spoke to seem divided on the usefulness of gauges. Half thought they were unnecessary, added bulk, and drove up cost. Why do you need a gauge if you know 100 pumps inflates your tire? But the other half liked them, because the “thumb test” is notoriously inaccurate.
Dennis Bailey has been actively involved in bike repair and maintenance for almost two decades. He has worked on bikes on bike tours in the United States, Europe, and Latin America. Keith Gates has been repairing bikes for more than 30 years and provides personalized service as the owner of A-1 Cycling, with locations in Manassas and Herndon, Virginia.
We rented a tandem bike from here for an hour, and they were super chill! We dropped by on a Sunday and decided to go eat first; Andy, one of the owners, was awesome about holding the bike for us while we went to eat before renting. We enjoyed our ride for just over an hr, but Andy was also super relaxed about our return time and only charged us for an hour. We had a fantastic time and would definitely recommend renting bikes from here!