| ??? 03/11/12 02:04 Modified: 03/11/12 04:17 Read: times |
#186573 - Some of your points are just wrong Responding to: ???'s previous message |
Per Westermark said:
The amount of force applied to a pedal do not vary so much with number of sprockets. Why? Because when it goes uphill you select a lighter gear but you still push what you can. Because the other riders will. So you stay at almost same rpm on the pedals. And almost the same force. It's only the torque at the backwheel that will be different since it's on the other side of the gear system. You cannot stay at the same RPM and same force applied to the pedals unless the power changes. power = torque X angular speed http://en.wikipedia.org/wiki/Torque EDIT: This should be the way that power is measured in this case. A simple solution to using a strain gauge would be to use strain gauges on the frame of the bike where the crank is located as the bearings holding the crank must be supported by the frame. The frame will flex to some degree. This removes your rotational strain gauge problem. Of course, some form of brain will be needed as the forces will be slightly split and would be a perfect job of an MCU to resolve. I still believe that this is a very difficult way of producing a torque value and would be more dependent upon the bike itself. |
