Dick, I'm aware of your credentials on the theory. My offerings were intended more to correct the answers offered by the other contributors than to educate you on matters aerodynamic, for which there is no need!
Though I'm no Cessna expert, the suggested figures you have been given for the 172 are in the right range (depending on weight), and they fit with my offerings on the 150, where most speeds will be some 15% slower.
Some old checklist notes, circa 1980 vintage, which I have to hand suggest the following climb (clean) speeds, which I wouldn't dispute:
C150 - 75mph
C152 - 70kts
C172 - 75kts
I personally went up in a 150 yesterday, solo, with 1/3rd tanks to check for you, and the figure I suggested seemed good, though testing it is an inexact science. Later last night, not a million miles from you, I was careful to hold Vref+20 to DA at Bristol RW27, with 20018G26 1000 S001 B002, on bigger metal - a very busy approach, so not the place to test for max glide!
R'gds to you, Alex et al
Last edited by pilotmike; 22nd Jan 2009 at 12:32.