I'm not sure, but there seems to be some conflicting aero data out there. The "Great Wheel Test" suggest that there's about 20W difference between a very good aero wheel-set and a shabby one. According to the Kreuzotter calculator, a 20W benefit, at or around 45kph, gives a rider a speed increase of about 0.7kph!!
http://www.kreuzotter.de/english/espeed.htm
This list of "aeroness", taken from a magazine, says that there's about a 15W aero benefit from the total 465W of rider drag, going from normal wheels to tri=spokes:
http://www.bikeforums.net/showthread...highlight=holy
This is a pretty big 3.23%.
.....I'm confused:
On the HED site, it says that an average rider creates about 6.5lbs of drag, of which, about 1/4 of a pound is from the wheels (3.8%). They also say, that in a cross/head wind of an angle of ~20 degrees, their HED JET 60 wheel (deep dish, 16 spokes) creates 218g of drag (doesn't add up so far
), compared to 294g of drag from a 28 spoke low profile wheel -- a 25% improvement just with the wheels. So, 25% from the 1/4 pound (3.8%) of 6.5 pound of total rider drag is less than 0.96%
http://www.hedcycling.com/wheels/stinger60.php
0.96% from the total 465W (from the "Holy Cow, Aero..." thread) is only a 4.46 watts.
Is all this just saying that tri-spokes are heaps better than 16 spoke, deep dish wheels?