So true. I used to commute in Canada at -30 to -40C on my Pugs and had far too many mornings of leaving the warmth of my apartment, rolling the bike downstairs, and getting 3 miles into a 7 mile commute before realizing I was pumping it really hard with pressures that were too low.
The danger at those temps was you needed to over-inflate so much that the first few miles were a little slick with the lack of footprint. I wanted to make a note about this though. From experience, even when studs are added, fat bike tyres are not the best on pure ice. My wife's studded 700/32 outperformed me there any day. However, in snow or frozen over slush/rough ice and ill take the fat bike.
Originally Posted by
Hypno Toad
I want to add this information to this thread - exposing things I 'know' but don't 'understand'.
I took a 25 mile ride at -10F earlier this month, it was a crazy amount of work (talked about above). I did not give enough thought to the change in temp and it's effect on the tire pressure. The night before this ride, I worked on the bike in the basement at ~65F checking tire pressure, moved it to the garage overnight, then took it on a ride at -10F. So, looking at the chart below, I started at 9psi at 65F, but when the tires cooled to -10F the pressure was down to 5.4 psi. That's a big difference!
Source:
Tire Pressure and the Cold: Bontrager's PSI Conversion Chart Will Keep You Inflated This Winter - Bikerumor
Oddly, I had just watched this episode of MythBusters that basically covering the same subject of changing pressure with temperature.