42/42 I don't ride once they salt the roads here, unless rain washes it away. Since most of us are running tires no more than 5 years old, decreasing the pressure to cause more flexing and increased heat buildup is probably not going to cause tire problems. However, I've not seen any tire manufacturer recommend this. My tires tend to heat up in any weather within a few miles, as shown on my TPMS, and I've never had adhesion problems riding in my lil ole conservative way. On the other hand, if you ride in a more spirited fashion, and you need all the grip you can get, maybe then you should stick to what works best for you. YMMV