ok I know this is a really dumb question with a very sensible answer. I am just a little bit confused about pumping up tire with my floor pump that has psi gauge on it. I know to pump it to 120psi, but when not pumping it settles at a reading of about 60. Am I supposed to pump so the needle peaks at 120, but is going to settle much lower when not pumping? Or is my gauge supposed to read 120 when not actually pumping? I hope this makes sense.<br />
Thanks
When your pushing down on the pump handle the pressure might spike and then settle back down. What happens is the pressure inside the pump goes way up, but as the air flows into the tire it goes down to what is now in the tire.
The pressure in the tire should be what shows after the gauge drops back down to a stable reading.
120 is pretty high. I assume that is what shows as the "max pressure" on your tire? On skinny racing tires, you probably don't want to ever go below 80-90. But you don't necessarily have to be at the max. Higher pressure means higher speed but harsher ride. Generally put about 5 psi more in the rear than the front as it has more weight on it.