[ax0n]

It's not that this isn't cool, because the gadget factor is pretty high... but normal (read: average fat American) people don't need this.

I'm a 230 pound dude. I'm probably 20-30% body fat. Heck, maybe more. I've put 5,000 miles on a normal bicycle in one year, including a 130+ mile ride in one single day on a mountain bike. I bicycle commute year round in Kansas City. This time of year I ride to the bus stop (5-7 miles round trip depending on my schedule and which buses I take) but quite often, I do the whole round trip by bike alone, which is 29 miles per day. I've driven to work once in the last 2 years. Almost all of my riding is for basic transportation, so I'm not one of those spandex-clad weekend-mile superheroes. I'm not fast, either. It's just efficient, and it makes sense most of the time. If I can do it without electric assist, pretty much anyone can.

That said, there's this whole "I'm Going Green™!" thing going on. And it's not that that's a bad thing either. Efficiency, sustainability and stewardship are great things.

This new wheel, however, actually makes the bike+human machine less efficient. It may have enough gee-whiz factor to get people to ride, but the chances of those people throwing their new hybrid-wheeled-bike onto the roof rack of their Hummer H2 and driving 3 miles to the nearest multi-use-path trailhead are probably rather high. I have my doubts it'll get many people to drive less and ride more.

[silentbicycle]

Yeah, it looks like something that exists so that people can feel like they're changing the world by buying something, rather than doing something that requires recurring effort and runs the risk of occasionally being boring.

(Also, 200+ lb. bike commuters represent!)

[10ren]

If it stored energy when braking, it would be more efficient.

But on my bike, I only really brake in rare situations, for safety reasons (cars); unfortunately, friction automatically supplies adequate braking for me.

I also choose paths that minimize braking. I guess it's possible that that might change if I had a bike that efficiently stored/applied energy, so that it was as if the braking hadn't occurred. But I don't think so; for one thing, it would be no where near 100% efficient.

[ZeroGravitas]

It's only more efficient if it regenerates enough energy from braking to compensate for the extra weight you're carrying which is highly unlikely, particularly extra weight on a wheel since that requires 1.5-2 times the energy to shift compared with the same mass added to the frame (http://en.wikipedia.org/wiki/Bicycle_performance#Kinetic_ene...).

You might still benefit if you need an electrical boost provided by energy from the grid but normal bikes hit a pretty sweet spot, so I'm thinking this is mostly gimmick.

[10ren]

Oh gimmick it is. It's just that the spring-sprung-brake concept has fascinated me since I was 5 yo. It would be cool to make this work; if sufficiently light, it would be a net win.

[jhancock]

Very impressive commuter story. I'm way too much of a cold wimp to ride a bike in winter.