Cool Crank Arms

[ChrisMac]

http://www.kickstarter.com/projects/1202837765/z-torque-bicycle-cranks-ride-faster-longer-easier

 

[scrumblero]

er..... what do they do besides look cool? :?

 

[CRASH]

Increased torque, so they claim. I'd want to try them first. If they truly work, I'd want them for my Tri bike.

 

[deorman]

BS :|

 

[Henry morgan]

anything but metal .. I would think if your making all the torque they are saying.. you would break them..
or at least I would... not sure... not sure about the claim of more torque anyway ..

 

[deorman]

The torque applied will be the same as a crank the length of the distance between the crank and pedal holes.

 

[Spincycle]

The torque applied will be the same as a crank the length of the distance between the crank and pedal holes.

Diddo. I didn't even watch the video. I knew if I did I'd be frustrated by the claims. Make the cranks as large and ugly as you want. What deorman said still stands true. I see a lot of lawsuits comming from broken castings. But then again what do I know.

 

[ozzmonaut]

The only way I can see any truth to the claim (I'm theorizing here, don't blast me) might be the weight at the bottom and how it is distributed. The increased mass at the lower end might help carry the crank around, and it being stretched out like that might be more aerodynamic. At least more aerodynamic than just adding mass to the lower end but having it occupy a space with a more bulky area. My friend built a perpetual motion motor with arms like that but with counterweights and springs and it actually worked. But it had 3 arms...oh , and springs and counterweights :lol: But even if the gains are so small that it is barely noticeable, it might allow them to make claims without a legal repercussion.

 

[danthrift71]

I would think, whatever mechanical advantage you have at the bottom of the stroke would be countered at the top of the opposite crank. Seems I recall some BMX company back in 80's or 90"s trying an "L" shaped crank. Some of you physics majors can probably explain the mechanics going on here.

 

[jackdaw]

The torque applied will be the same as a crank the length of the distance between the crank and pedal holes.

Yup. That's just silly. Neat looking though.

 

[Carbon]

That z shape would be cool for the bmx or roadie guys but they'd have to make a half moon design for the old schoolers with curved frame bikes. :lol:

 

[jwm]

This reminds me of those oval shaped front sprockets. I used to have a GT Karakorum MTB that had them. It was a great bike, but I don't think the oval sprocket really helped much.

JWM

 

[Henry morgan]

the more I think about this . the more I wanna throw a flag on the play .. sorry family site..
I dont think this will work reguardless of what the material its made from .. your still pushing your 2 feet around in a circle
its more an issue of how the human body works.. then the design of the cranks. your leg does not bend in a manner
that allows your foot to continue applying force on the back side of the stroke. there are ways to cheat .. but really
only applys to fixie bikes... and cleated shoes... you can push and pull... i just dont see how these could work..

but then I do wear thick glasses

 

[yoothgeye]

I'm glad everyone has said the same thing I was thinking as I watched the video, it's bull. Imagine this, instead of making a crank arm, make a disc, put the pedal hole anywhere you want at an equal distance from the spindle hole as a regular crank arm, make all the claims you want, it's just an overpriced weird shaped crank arm that got the inventor excited enough to pedal harder when he rode his "Next" bicycle.

What 2 colleges tested these things? Clown and Barber?

 

[Carbon]

Well,... if you concider the curculeye nebulous of the ratcheting convolution where as the centralised mass or the centrifugal force is therefore applied when the rotation of ones leg is proportionate to warping time and space, this could make for very relevent exertion of applicable forward motion confirming effectiveness. For those wondering, I'm just saying,... :lol:

 

[user 135]

Crank arms have been through this rodeo before.
In 1724 http://www.besslerwheel.com/forum/downl ... 119c141520

1932 http://bikeville.blogspot.com/2011/04/c ... ranks.html

1983 http://www.classicrendezvous.com/Italy/PMP_crk_ad.htm

2009 http://www.bikerumor.com/2009/07/22/cur ... fficiency/

 

[Henry morgan]

Well,... if you concider the curculeye nebulous of the ratcheting convolution where as the centralised mass or the centrifugal force is therefore applied when the rotation of ones leg is proportionate to warping time and space, this could make for very relevent exertion of applicable forward motion confirming effectiveness. For those wondering, I'm just saying,... :lol:

What u talking about willis. Oh u mean the time space continuem

 

[deven_science]

Some of these past curved/bent crank arms may not give any mechanical advantage... but this does bring something else to mind. The cranks are usually one of the few parts on a bike that always looks the same. Some curved or bent cranks might give an extra bit of customization. I might need to try to find some nice curved ones that will blend with the curves on the frame.

 

[user 135]

Some of these past curved/bent crank arms may not give any mechanical advantage... but this does bring something else to mind. The cranks are usually one of the few parts on a bike that always looks the same. Some curved or bent cranks might give an extra bit of customization. I might need to try to find some nice curved ones that will blend with the curves on the frame.

Roadmaster made some too. viewtopic.php?f=16&t=34696&p=339299

 

[Toeslider]

I'm shocked in this day and age that people get behind something like this without applying even the slightest bit of common sense.

Allow me to bypass the endless dialogue and blow a giant hole in this mans theory (red line added by me):

If someone can explain to me how the relationship of these two holes to each other will ever change, I will eat my shoe. It's just a triangle with a missing side.