fish@ihlpg.UUCP (Bob Fishell) (07/17/85)
*** AC T YOUR AGE *** I just re-wheeled my bike and went to 100-psi tires with presta valves. I had no trouble inflating the tires, but I can't tell the tire pressure by looking at the gauge on my foot pump any more. Presta valves operate by air pressure, so the valve doesn't stay open to move the gauge. I have been estimating pressure by the trusty "thumb" method, but I'd sure like to know what the actual pressure is. Anybody have experience with gauges or pumps that will do the trick? __ / \ \__/ Bob Fishell ihnp4!ihlpg!fish
mascagni@acf4.UUCP (Michael Mascagni) (07/19/85)
/* acf4:net.bicycle / fish@ihlpg.UUCP (Bob Fishell) / 5:19 pm Jul 16, 1985 */ >I just re-wheeled my bike and went to 100-psi tires with presta valves. >I had no trouble inflating the tires, but I can't tell the tire pressure >by looking at the gauge on my foot pump any more. Presta valves operate >by air pressure, so the valve doesn't stay open to move the gauge. > >I have been estimating pressure by the trusty "thumb" method, but I'd >sure like to know what the actual pressure is. Anybody have experience >with gauges or pumps that will do the trick? > __ >/ \ >\__/ > Bob Fishell > ihnp4!ihlpg!fish I own a pressure gauge for presta valves. It was purchased at Stuyvasant
brooks@lll-crg.ARPA (Eugene D. Brooks III) (07/20/85)
> I just re-wheeled my bike and went to 100-psi tires with presta valves. > I had no trouble inflating the tires, but I can't tell the tire pressure > by looking at the gauge on my foot pump any more. Presta valves operate > by air pressure, so the valve doesn't stay open to move the gauge. Get a good quality pump with a gauge and use good presta valves. The pressure in the tire will be the gauge pressure after the air has leaked into the tube. The gauge needle jumps up to get the required opening pressure but as air flow stops across the valve the pressures are nearly equal. This gets ride of the rather large opening force error. There is of course some small error left but its only a pound or two and therefore not significant.
hansen@utah-cs.UUCP (Chuck Hansen) (07/23/85)
I use a Schrader (?) type adaptor on my Presta valves when I want to check the pressure. It's not very elegant but functional! Chuck Hansen ...utah-cs!hansen