want to try 10 speed bike style 'transmission' for power generation

Discussion in 'The Projects Forum' started by robwill, Jul 27, 2013.

  1. robwill

    Thread Starter New Member

    Jul 27, 2013
    hello! I am researching cheap energy for my home. I am looking at gravity and wind and solar. Solar, I need no assistance with 'gearing', clearly. but, for wind or gravity, I am thinking that RPM's and torque are mutually exclusive, so to speak. I could, in theory, get a wind spun device to turn 'something' at a 1 to 1 ratio, and I suppose I would have the same torque as the power of the imput. and, I have seen many people do experiments with gearing, such as 10 speed bike style small-to-large RPM up and down conversion. a lot of people smarter than me always say, even if the 'speed' of the spinning wheel has been increased thru different size pulleys or gears or anything, it still is in effect the same torque. I want to increase the torque for any given RPM. if all gearing or pulleys are static, they stay the same, then an 'artificial' increase in speed is reducing the torque at the same ratio as the speed increase. so, what if I could devise a way to increase RPM kinda controllably, with (as an example) a ten speed bikes' system of sprockets? then, could I assume I am actually getting more torque as I get the driven devise up to speed over time with the input device being not slowed down because of the 'transmission' and gradual changing of 'gears' as in a ten speed bike? thoughts?
  2. crutschow


    Mar 14, 2008
    Gearing changes the speed and torque at the same ratio. So if you increase the speed, you reduce the torque and vice-versa. There is no also no change in the power transferred (i.e. there's no free lunch) except for friction losses.
  3. WBahn


    Mar 31, 2012
    I would not recommend a 10-speed bike set up. Have you ever changed gears while applying your full weight to the pedals? Probably not. You easy up almost completely on the power you are delivering to the pedals and change the gears under only a very light load. Then again, people may have come up with a way to deal with that issue through a clutch or something else.