I know I am biased, but I believe that this is a fair description :)
What is the difference between Rotor Cranks and Powercranks?
How Rotor Cranks work - and the benefits:
Rotor Cranks work by increasing the force required on the drive side crankarm which propels the non-drive crank are past the 12 o'clock point ... also known as the dead point. This happens 180 times a minute in a 90RPM ride. Over 10,000 times an hour. The cyclist is now "permanently pushing" the cranks as there is no gap between when the legs take over push/recover duties. This elimination of the dead point makes pedaling more efficient, reduces muscle requirements to complete the pedalling revolution, and reduces lactic acid in the bloodstream. The reduction of lactic acid allows the rider to produce more wattage at his/her lactate threshold. It "raises the roof" if you will, you can crank out more wattage before hitting LT. The extra wattage is converted to speed in the amount of 2-3 minutes per 40k.
How Powercranks work - according to their web site:
PowerCranks teach your neurologic system to unconsciously "pedal in circles." By pedaling in circles, more of the energy you are now expending actually gets to the wheel. For the same overall effort, the more efficiently you pedal, the faster you go. So the cyclist gets more efficient use of the muscles he/she has already trained and, as noted above, the ability to incorporate new muscle mass into the now unused portions of the pedal stroke. Powercranks are based on "pulling" up on the pedal stroke using the weaker hip flexor muscles. Unlike normal cranks, each crank arm spins independently of one another.
Difference between Rotor Cranks and Powercranks:
Rotor Cranks eliminate the dead point, allowing for "permanent push" to the pedals, making legs efficient at what they do best: pushing. This allows for lowered lactate levels and increased wattage at LT, which translates directly to the 2-3 minute per 40k speed increase. They are scientifically proven to reduce lactate levels, reduce cardiac effort, and improve the health of a cyclists knees by eliminating the dead point.
Rotor Cranks are not perpetual motion machines and do not claim to increase power by 40% (for more information on this topic, ask Kraig Willet about the Redshoe Brand Shoes he has been using). As we all know, there is no such thing as "free power" in cycling, especially a 40% gain just by using a set of cranks, there is a tradeoff here. Rotors do however make a claim to lower lactate levels and heart rates. They do not raise your power without the rider having to apply more resources for the mechanical advantage, and then by 16 percent net gain, but they offer you the opportunity to ride harder and at a higher wattage output - before reaching your lactate threshold. For a TT'ist or Triathlete, this is important. Your lactate threshold is probably your biggest limiter for trained athletes in endurance cycling events.
Powercranks give you an immediate feedback system as to when you start to pedal improperly so you can retrain your neurological system to fire your muscles in a different coordination changing the pedaling dynamic to improve pedaling efficiency. They are great for developing a smooth and efficient spin and are a much better alternative than one-leg pedaling drills. They improve the strength of hip flexor muscles which benefit running and "lifting the leg".
Last edited by:
Gary Tingley: Feb 5, 04 13:02