How much air goes from the tire to the pump when you plug it on the valve?
04-26-21, 05:53 PM
#101
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04-27-21, 05:42 PM
#102
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The formula you want is: PV = NRT. Your basic chemistry text will show how to use the fudge factors (N and R). But the rest is self-explanatory.... pressure times volume at temperature T in the bicycle tire is equal to that in the pump
04-27-21, 06:12 PM
#103
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You don't need N, R, or T. P_1V_1=P_2V_2. So pressure in pump+tire equals pressure originally in tire times the ratio of the volume of the tire to the volume of pump plus tire. That assumes things go slowly enough that pressure has stabilized. If not, things get messy fast.
Last edited by asgelle; 04-27-21 at 09:02 PM.
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04-28-21, 07:24 AM
#104
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04-28-21, 07:30 AM
#105
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Step 1: Get rid of the anal retentiveness.
Step 2: Pump your tires to the recommended psi or preferred psi for comfort.
Step 3: Toss your OCD to the side and just accept the fact that the actual pressure that any gauge reads will be ±5 psi from the actual pressure in the tire.
Step 4: Get on your bike and ride and now enjoy your new stress free life where knowing what the tire pressure is isn't a big deal.
Step 2: Pump your tires to the recommended psi or preferred psi for comfort.
Step 3: Toss your OCD to the side and just accept the fact that the actual pressure that any gauge reads will be ±5 psi from the actual pressure in the tire.
Step 4: Get on your bike and ride and now enjoy your new stress free life where knowing what the tire pressure is isn't a big deal.
04-28-21, 02:41 PM
#106
Newbie
Relatively easy calculation using ideal gas law. P1*V1 = P2*V2, where P1 is your tire pressure and V1 is your tire volume, V2 is your combined volume of tire plus gage, and solve for P2. Don't worry about the units as long as you are consistent on both sides of the equation.
04-28-21, 09:10 PM
#107
Newbie
04-28-21, 09:12 PM
#108
Newbie
