The Oil Drum

No toeclips? You’re wasting a whole bunch of efficiency there. By using your upstroke you can gain much more power.

Power, maybe. Efficiency, no. You use energy when pulling the pedal up with your leg, energy you wouldn't otherwise use if you were just coasting with it on the up swing. Not knowing anything about anatomy and muscular dynamics, but it might actually be less efficient since the muscles in the human leg aren't meant to pull up loads other than its own weight under any evolutionary circumstances.

Anyway I use the heavy military bicycles to offset my otherwise sedentary lifestyle, so maximizing efficiency would mean I wouldn't get the same exercise as before. In fact I don't understand some cyclists with their over thousand euro super bikes with gazillion gears and carbon fiber frames. Surely if you want to get fit and be 'sporty' you should pick the heaviest bicycle you can possible peddle with? And the speeds they reach begin to be quite dangerous, at least to other cyclists. And if they want efficiency they should stick with speeds under 25km/h since above that you actually waste most of your pedaling effort into forcing air out of your way.

I haven't seen the likes of the military style bikes. I presume they have traded off weight and efficiency for robustness and reliability. It looks like they have 1.5 to 2 times as many sokes, so I suppose you could carry a very heavy load without damaging the bicycle.

Toe clips do help, the amount of extra muscles recruited are at the discretion of the rider. I used to do tons of mountain biking, on ridiculously rocky terrain, I never was unable to get out of clips when falling off. But not being clipped in, and you are likely to lose control as your feet are bounced off the peddels. At high output levels, toe clips allow you to generate more power, or less leg strain at a fixed power level. Clipins are slightly more effcient than clips, but I never mastered getting out of them -especially if I tried to stay upright until the last possible half second.

The hard core "trials riders" didn't use clips, but instead used platform pedals. They could do amazing things with their undersized bicycles. But trials setups would be horribly inefficient to ride for any sort of distance.

There's a graph in that book comparing energy efficiency of different animals/vehicles.

Any chance you could scan/photograph that in here?

Part of the efficiency of the average human depend upon the food the human has eaten and how "efficiently" (or, along another line of thinking, how many fossil fuel inputs) were involved in it?

If you're eating that locally grown organic food, your big picture energy efficiency is higher than if you eat an industrialized agriculture diet, with strawberries from 8000 miles away, etc.

Over a meal after an event here in San Francisco a couple years back, Richard Heinberg brought this up, saying that all things considered (the average diet) an electric bicycle actually was more "efficient" (right now) than a human powered bicycle.

This was not in any way an "endorsement" of electric bikes or condemnation of human bikes, just a statement about efficiencies in the world as it is set up.

Which is why I already have a lifetimes worth of IDENTICAL or COMPATIBLE bike spares - think ahead: "oh those - no they went bust years ago.."
Keep the tyres dark and cool. Choose your chainrings with old man muscles in mind, 1 steel one per decade of future cycling, and plenty non-indexed shifters.

I would start collecting soon, because I was buying cards of red rubber brake blocks and spare Suntour jockey wheels when they were made 25 years ago..