aumy.wood
13-09-2012, 10:18 AM
Một website giới thiệu sản phẩm "Rotor Cranks", mà theo họ là tăng hiệu suất đạp xe.
http://www.cyclecraftsg.com/Product_Pictures/Rotor/MTB_simulator_sml.gif
Trích: http://www.cyclecraftsg.com/RotorCrank.html
"Rotor Cranks work by slightly increasing the force required on the drive side crankarm during the pedal downstroke, using this energy to propel the non-drive crank are past the 12 o'clock point (also known as the dead spot). This happens 180 times a minute in a 90RPM ride. Or 10,800 times an hour. This might sound as if we're just transferring energy from one leg to the other, to no gain. But that conclusion is wrong: by throwing the leg in the last 50 degrees of the revolution over the dead spot, you enable that leg to apply more power earlier, leading to a net gain in power output.
With ROTOR Cranks, the cyclist can "permanently push" the cranks, as there need be no gap between when the legs take over push/recover duties, otherwise known as the dead spot. All the same, this doesn't eliminate the "rest time" for your legs, because you dont put any force into the pedal stroke in the last section of Rotor is an innovative pedalling system that eliminates the dead point using an ingenious cam system. The dead point of conventional pedalling is the point when the pedals are vertically positioned (one at the top and the other at the bottom). At this position, neither leg can transmit any power.
The dead point limits the cyclist's performance, causes tendonitis and injuries to the knee. It is also a major source of lactic acid buildup and causes a major discontinuity during each pedal revolution. Rotor System resolves this inefficiency problem by eliminating dead points.
Rotor makes the cranks independent in such a way that they are not aligned at a fixed 180º, but rather the angle between them varies during the cycle so that one pedal never coincides with the one below at the dead point, thus avoiding power vacuums. Such an effect is achieved by the use of independent cranks that are synchronised by means of an exocentric axel and two rods, which vary the development during the cycle and adapt to the muscle power of the legs at all times. By eliminating the dead point, Rotor optimises the effort of the cyclist and reduces the risk of injury, providing a notable increase in performance and more comfortable and healthy pedalling."
Về nguyên tắc thì thấy cũng có lý, nhưng baphi thấy lạ là chưa nghe nói có tay đua nào dùng cả. Có bạn nào biết gì về nó không?
http://www.cyclecraftsg.com/Product_Pictures/Rotor/MTB_simulator_sml.gif
Trích: http://www.cyclecraftsg.com/RotorCrank.html
"Rotor Cranks work by slightly increasing the force required on the drive side crankarm during the pedal downstroke, using this energy to propel the non-drive crank are past the 12 o'clock point (also known as the dead spot). This happens 180 times a minute in a 90RPM ride. Or 10,800 times an hour. This might sound as if we're just transferring energy from one leg to the other, to no gain. But that conclusion is wrong: by throwing the leg in the last 50 degrees of the revolution over the dead spot, you enable that leg to apply more power earlier, leading to a net gain in power output.
With ROTOR Cranks, the cyclist can "permanently push" the cranks, as there need be no gap between when the legs take over push/recover duties, otherwise known as the dead spot. All the same, this doesn't eliminate the "rest time" for your legs, because you dont put any force into the pedal stroke in the last section of Rotor is an innovative pedalling system that eliminates the dead point using an ingenious cam system. The dead point of conventional pedalling is the point when the pedals are vertically positioned (one at the top and the other at the bottom). At this position, neither leg can transmit any power.
The dead point limits the cyclist's performance, causes tendonitis and injuries to the knee. It is also a major source of lactic acid buildup and causes a major discontinuity during each pedal revolution. Rotor System resolves this inefficiency problem by eliminating dead points.
Rotor makes the cranks independent in such a way that they are not aligned at a fixed 180º, but rather the angle between them varies during the cycle so that one pedal never coincides with the one below at the dead point, thus avoiding power vacuums. Such an effect is achieved by the use of independent cranks that are synchronised by means of an exocentric axel and two rods, which vary the development during the cycle and adapt to the muscle power of the legs at all times. By eliminating the dead point, Rotor optimises the effort of the cyclist and reduces the risk of injury, providing a notable increase in performance and more comfortable and healthy pedalling."
Về nguyên tắc thì thấy cũng có lý, nhưng baphi thấy lạ là chưa nghe nói có tay đua nào dùng cả. Có bạn nào biết gì về nó không?