Flywheel for Bicycles

(BretCahill) may have said:

Here in the Sonoran Desert anti-thorn measures typically result in a bicycle wheel that, when
rotating at 8 mph, has an angular momentum that would rival Jupiter's.

This wouldn't be such a problem if the brakes could somehow spin a flywheel to save the otherwise
wasted energy for a nice quick acceleration after the light changes or after the mountain
switchback.

Is anyone doing anything with this? My knees need to know.

Wouldn't help. You'd be adding *significant* mass and complexity to the bike, and the problems
inherent in trying to use a flywheel as a brake for inertial storage would make a lot of engineers
want a long vacation in a quiet place afterwards. (Carmakers have tried flywheel-restart systems to
allow engines to be stopped at traffic lights; they have never worked well enough to become common,
although a small number have actually made it into production vehicles at times.)

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BretCahill said:

Here in the Sonoran Desert anti-thorn measures typically result in a bicycle wheel that, when
rotating at 8 mph, has an angular momentum that would rival Jupiter's.

This wouldn't be such a problem if the brakes could somehow spin a flywheel to save the otherwise
wasted energy for a nice quick acceleration after the light changes or after the mountain
switchback.

Is anyone doing anything with this? My knees need to know.

Bret Cahill

I think you'll find upon reflection that the kinetic energy in your thorn-resistant wheels is
tiny compared to the combined moving mass of bike and rider -- Jupiter notwithstanding. So your
problem is little changed by the thorn issue and is the same as faced by all riders. Since it
takes relatively few concerted strokes to get up to speed after a stop, it would seem that any
regenerative braking system that has to be hauled up hills is going to have a hard time paying
for itself.

Quoted message said:

Werehatrack <[email hidden]> in

Quoted message said:

Message-id: <[email hidden]> writes:

. . .

Quoted message said:

You'd be adding *significant* mass and complexity to the bike, and the problems inherent in trying
to use a flywheel as a brake for inertial storage would make a lot of engineers want a long
vacation in a quiet place afterwards.

Energy storage tactics might be better suited to the electronically pulsed electric motor bike that
was recently under discussion.

Bret Cahill