I’m curious: Does anybody believe the claim that a Z shaped crank can provide more leverage because it’s longer?
I hope it doesn’t take an advanced education in physics to realize why the shape of the lever arm doesn’t matter, only its distance from the lever does, but here’s the detailed discussion if you need more convincing.
The inventor, Glenn Comment, apparently was inspired to design this crank in a dream after a frustrating day biking to a friend’s house into a stiff headwind. He kept shifting down into a lower gear to get through the headwind. Comment’s inspired solution: create a longer crank arm (which is equivalent to shifting to a higher gear, but never mind that), and then keep the spinning diameter the same by bending it into a Z shape. Because of the big elbow bend on that crank, you also get much less cornering clearance. Instead of a pedal strike, you’ll have the crank itself strike on the pavement. That should be exciting!
Comment and his family market these cranks as “Z-Torque” and they’re available for sale for $270 for a set. They’re expensive because each set of cranks is machined out of a block of solid aluminum.
Z-Torque’s first attempt to reduce prices through mass production was via this Kickstarter project. 27 people ponied up over $75 each to support the project, but they still fell far short of their $50,000 funding goal.
The Kickstarter campaign fell short by about $43,000, so they’re trying again at another crowdsourcing site. If they succeed, Z-Torque plans to supply a team with these cranks for the Cigar City Criterium in Tampa, Florida. Z-Torque also says the cranks are designed to fit standard (which one?) square tapered spindles.
Friends have undoubtedly explained the physics to the Comment family. Many of the comments left on Z-Torque’s YouTube channel and elsewhere on the Internet are brutal. This family’s willingness to soldier on is a testament to the universal human ability to believe the goofiest things.
Prior art going back to 1897! Didn’t work then, either. http://www.retrobike.co.uk/forum/viewtopic.php?t=58567