Originally Posted by
prj71
Which is what makes it useless chart for most to use. If my bike was stored inside at 70 degrees and my tires are at 10 psi it tells me that at 10 degrees my tires would drop to 7.2 psi. Now lets say I get to the trail and it's soft conditions after recent grooming. If I'm a 225 pound guy I'm probably going to have to lower the pressure so I don't put ruts in the trail. If I'm a 165 lb guy the pressure is probably OK where it's it and then there is everything in between. Now if I get there and the trail is hard packed maybe the tires are ok where they are or a little air could be added. Then there is the other variable that chart doesn't consider...are the tires 3.8" wide or 4.6" wide which also affect things.
Really too many variables between temperature, rider weight, tire width and snow conditions to make that chart worth while. It's easier to pump the tires up to about 10 psi before leaving home and then decide to leave alone or let more air out once the destination is reached.
This chart is to convert a pressure from an indoor temp to an outdoor pressure, that's all, end of story. You need to know a target pressure for the conditions you'll be riding, but I said that in my last post.
Fun fact, not every single person rides a fatbike exclusively on groomed trails 🙄. Rules for tire pressure on groomed trails don't apply while riding on ice, hard pack, or hardpackedice. Look at the OP, we are not talking about a 10* change in temp, we are talking about 70* to 80* change in temp. Sunday morning, I rode out with temps around -15F on a 30+ mile ride on ice covered plowed trails. I needed a higher pressure so the studs could bit into the bulletproof ice, so you're repeated posts about riding groomed trails aren't worth while.
Originally Posted by
Hypno Toad
This forecast has me planning for the weekend
Your arguing about something totally different, this pic is for your conversation:
Your point is not *wrong*, your point is simply in the wrong thread. If you have nothing to add to the conversation about the change in fat tire pressure when taking a bike out of a warm space in to a very cold place, move along. kthxbye!