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You are now stupider for having looked at this (warning bieks)

Da Peach

Da Peach

Outwitted by a rodent
Jul 2, 2002
13,683
4,912
North Van
If I were a crank designer, I'd learn to spell "pedal".

That said, I'd love to be a beta tester.
 
eaterofdog

eaterofdog

ass grabber
Sep 8, 2006
8,292
1,535
Central Florida
I think this is great, 150 years of bicycle design still hasn't given us any way to increase torque at the crank.

If he had ever accidentally bumped the shifter on his bike, this never would have been invented.
 
jonKranked

jonKranked

Detective Dookie
Nov 10, 2005
85,859
24,451
media blackout
eaterofdog said:
I think this is great, 150 years of bicycle design still hasn't given us any way to increase torque at the crank.

If he had ever accidentally bumped the shifter on his bike, this never would have been invented.
Click to expand...
he probably uses the auto-shift system that's a bunch of weights on the wheels.
 
4130biker

4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
449
What a dumbass, the z bend obviously needs to be pointed the other direction for maximum power output.
 
HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
6,721
5,604
Are the carbon ones just done in some sort of editing software or are they just wrapped alloy cranks? Either way they don't look right.
 
4130biker

4130biker

PM me about Tantrum Cycles!
May 24, 2007
3,884
449
I'm guessing it's their representation of what the carbonz versions will look like when they're done... Anyone watch the vid?
 
Westy

Westy

the teste
Nov 22, 2002
54,396
20,187
Sleazattle
Ithnu

Ithnu

Monkey
Jul 16, 2007
961
0
Denver
That made me feel like those people who forget order of operations on stuff like 4+1x0 and think it equals zero.

Or is that whole thing a joke?
 
HardtailHack

HardtailHack

used an iron once
Jan 20, 2009
6,721
5,604
Ithnu said:
That made me feel like those people who forget order of operations on stuff like 4+1x0 and think it equals zero.

Or is that whole thing a joke?
Click to expand...
I just had to check that, I thought maybe it ends on the 1st of April like that stupid light box camera thing last year but sadly it seems this one is legit.
 
Pesqueeb

Pesqueeb

bicycle in airplane hangar
Feb 2, 2007
40,298
16,738
Riding the baggage carousel.
Via Reddit:

Investors beware, when something sounds too good to be true, it usually is. Right now an entrepreneur is asking for money to manufacture bicycle parts that he says will give cyclists more power, even though the way he claims it works is contradicted by the laws of physics.

The cranks of a bicycle are what connect the pedals to the front gears. They're lever arms that cyclists exert a force onto the end of, through the pedals, in order to turn the front gears. The front gears pull the chain which then spins the rear wheel, sending the bike speeding along.
Just about all the cranks on the market are a straight line from the pedal to turning radius. However a company called Z-Torque claims that their cranks give cyclists more power just by changing the crank arms into a bent shape. The problem is that physics doesn't work like the company claims it does.

The inventor, Glenn Coment, claims that his zig-zag design gives peddlers more leverage resulting in more power, but keeps the pedals at the same distance away from the center of rotation. However even a basic understanding of how levers work would show that this is impossible.

In his fundraising video, he gives a brief physics lesson about how his cranks supposedly work.

“Pedaling your bike is similar to using a wrench to tighten or loosen a bolt. Any mechanic will tell you if you need more torque to loosen a stubborn bolt, just go get a bigger wrench. That’s because by moving your applied force further away from the pivot point, you gain more leverage," Coment said.

So far he's right. Torque is the twisting force a rotating lever or wheel exerts on its axis. Increasing the length of a lever arm, like a wrench, exerts more torque on its bolt. The longer the lever arm, the more torque is produced by the same amount of force pushing on the end of the lever.
The same would be true with bicycle cranks, which are fundamentally the same as levers. One could get more torque with longer cranks, but the cyclist would have a greater distance around to pedal. The problem of course is human legs are only so long, and there's no real comfortable way to make the cranks significantly longer without people being unable to reach the pedals.

"That’s why with the patented Z-Torque bicycle crank we have solved that problem for you," Coment claims. "You see we extended the crank arms past the length of a standard crank, giving you more leverage, but we then brought pedal back towards the axle to keep your rotation at the same diameter.”

He incorrectly claims that a cyclist can get more torque by having a crank arm that's "longer" but bends back towards the center, keeping the pedals the same distance away from the axis as a traditional straight crank. Levers don't work like that. It doesn't matter what shape the lever arm is, it only matters how far away the pedal is from the center of rotation.

“Having a wiggly line between one and the other doesn’t do anything about the torque," said David Gordon Wilson, an emeritus professor of engineering at MIT and author of Bicycling Science. “The tortuous form of the crank is just crazy.”

He said one could imagine welding a piece of aluminum straight between the pedal and the axis of rotation on the angled cranks. The leverage of the cranks would be the same whether the crank arm is straight, angled curved, or any other shape. The only thing that matters for leverage is how far the pedals, the source of the exerted force, is from the axis of rotation.

“This Z-crank has no redeeming features whatsoever,” Wilson said.

Coment's design isn't new, designs for curved or angled cranks have been around since the 1930s. He's had prototypes for his Z-Torque cranks since 1995, a patent on them since 1999, and a website selling aluminum versions since at least 2009. Recently he's been trying to expand and make carbon fiber versions. In September of last year, Coment launched a Kick-starter project to raise $50,000 to buy tools and equipment, but missed his goal by more than $47,000. He's now trying again, on a different crowd-funding website, "Rock the Post" with a more modest $7,500 goal.

The website also claims that the cranks give riders "Less perceived effort to pedal." In the medical world, I think they would call that a "placebo."
http://physicsbuzz.physicscentral.com/2013/01/bad-physics-bad-investment.html
Click to expand...
 
PepperJester

PepperJester

Monkey
Jul 9, 2004
798
19
Wolfville NS
Showed this to my girlfriend and her reply was .... "What the hell is this???"


But really this must be some sort of joke, what kind of person could possibly use an shot of biker fox in a serious promotional video?
 
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