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Selle Italia advert
The advert at the top of road.cc says the new Flite friction free saves 0.7w per pedal stroke (which doesn't make any sense, because wattage is power/time, but is that another matter?), gaining an increased 3% in speed... 3% of 23 is 0.7. Are they saying they have gauged this on someone producing 23 watts. Actually, let's triple to 2.1 watts. That for someone pedaling at 90rpm (three strokes per second). Are they saying the average cyclist produces 69 watts? Also, to increase the speed by 3% at 20mph, due to the air resistance being the square of velocity, would probably be much more than a 3% increase in power. Let's say 6% because I can't be bothered working it out. Which makes our hypothetical cyclist's output 35 watts or so.
Can someone from Selle Italia explain the maths in the advert to me?
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It's quite simple really, and explained fully here:
http://star.psy.ohio-state.edu/coglab/Miracle.html
Brilliant! Not at all what I'd expected from that link, but then I didn't pay attention to the file name. The artist must have re-copyrighted that cartoon, though. I've got it on a t-shirt which, I'm pained to admit, dates from long before 2006.
Yes, I think the cartoon goes back to the 40s or 50s. It looks like something from The New Yorker.