The exercise bike has a 20 inch bike wheel
the original tire was a solid sponge rubber, not
very good for a friction driven generator to be
running against, luckily a regular bike tire and
tube fit on it, had to drill a hole in the rim
for the tube stem...minor detail.
I made an 1 1/2 wood pulley for the little
generator, so everthing considered I calculate
that if I pedal at a 60 rpm rate, the wheel spins
at 120. This would be about 7mph and the generator is spinning about 1920rpm (crank to
generator ratio 1:32)
This seems to be very inefficient....I'm
putting about 800Ma into 6 700Ma AA batteries
at about 9.5 v0lts or about 7 watts.
I'm handcranking this and exerting as much
energy as I was in physical therapy at 50 watts
according to the meter on their machine.
I figure that if I hooked a 30 volt Ametek to
the wheel with a 3 inch dia. pulley then pedaling
at a 7mph rate...60 rpm the Ametek will be spinning about 1000 rpm and I'll be charging a
12 volt battery at least 30 watts??
Is my math about right? ....over or underestimating ?
What is the best operating range for a 30 volt
Ametek?