Floor pumps have a dirty secret. They all have pressure gauges that are only sorta accurate when they’re in the middle of their pressure range. So if you have a pump that goes to 150, it’s not very accurate above 130 or below 30. In fact, it can be wildly off. Even most pressure gauges suffer from this problem to an extent. So if you have a 0-60 pressure gauge, and you are trying to use it set up a fat bike, sorry bub, it’s not gunna be very accurate.
As pressures get lower, you need more accuracy. That’s because there is only a 22 percent different in tire pressure between 100 and 80 psi, (a 20 pound difference), but there is a 24 percent difference between 32 and 25 psi (a 7 pound difference!). As pressures drop, the percent change between each number becomes bigger. A fat bike running 3 pounds of air vs 2 pounds (I ride 3 pounds, Candice rides 2), is a whopping 40% difference. Yet a floor pump can not detect that change! So you need a gauge. Ideally, you need one for really low pressures if you have a fat bike (0-15), one for your mountain bike (0-30psi), and one for your touring bike (0-60psi). Each gauge is a master at the target psi range.
Seems crazy, right? 3 gauges for 3 bikes? I know plenty of folks who have different shoes for each bike though, and that’s way more expensive. These are affordable, brass construction, nice looking, and they’re accurate. If you use them properly, you can dial your tire pressure in, and keep it consistent. That means a better ride, every time.
For presta valve only.