Go Back   RCCrawler Forums > Miscellaneous > Chit Chat
Loading

Notices

Thread: The Z Torque Bike Crank-Breaking Laws Of Physics

Reply
 
LinkBack Thread Tools Display Modes
Old 10-04-2012, 02:21 AM   #1
I wanna be Dave
 
Join Date: Dec 2009
Location: San Francisco
Posts: 2,236
Default The Z Torque Bike Crank-Breaking Laws Of Physics

Man, either these guys are really dumb enough to think that it works or they are trying to capitalize on other peoples stupidity.

Quite hilarious, even after a few good explanations written in the comments by actual engineers cant convince these guys that they are wrong.



Z-Torque Bicycle Cranks - Ride Faster ! Longer ! Easier ! by Jason Coment — Kickstarter
SMR 510RR is offline   Reply With Quote
Sponsored Links
Old 10-04-2012, 02:27 AM   #2
Rock Stacker
 
Join Date: Aug 2012
Location: Spokane Wa
Posts: 55
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Looks like an interesting idea, would love to see the studies that they did as well as some strength tests compared to a straight crank
Hitman Cody2130 is offline   Reply With Quote
Old 10-04-2012, 03:07 AM   #3
Rock Crawler
 
Join Date: Feb 2007
Location: CoMo...Kickin it with Holmes Hobbies
Posts: 805
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

all that he achieved was to actually shorten the crank.
ROSS is offline   Reply With Quote
Old 10-04-2012, 03:47 AM   #4
Quarry Creeper
 
Join Date: Sep 2010
Location: Deus est mortuus, logica obtinet.
Posts: 451
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

haha this is hilarious. i'm not worried about it, there is simply no way they will hit their $50k goal and all money gets refunded if the goal isn't met. it's just funny how terribly flawed their list of advantages is. the only advantage would be aesthetics. it looks kinda cool, but there is no real benefit to it. kinda like studded belts, they look different but the studs don't hold your pants up.
ohh EPiC FAiL is offline   Reply With Quote
Old 10-04-2012, 04:04 AM   #5
Pebble Pounder
 
Join Date: Apr 2007
Location: va beach
Posts: 171
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Looks like something you'd see all polished up on a lowrider bike!
execelon is offline   Reply With Quote
Old 10-04-2012, 06:46 AM   #6
RCC Addict
 
Join Date: Feb 2005
Location: Crawlifornia Uber Alles
Posts: 1,146
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Garbage. Especially with the square taper holes for the bottom bracket.
gregrocks90046 is offline   Reply With Quote
Old 10-04-2012, 07:20 AM   #7
I wanna be Dave
 
Join Date: Nov 2010
Location: 07456 N. NJ USofA
Posts: 8,314
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Sheesh......

1-I can't believe people think this is, "The way to go in the future".

2-I can't believe people are backing this.

Then again, people here are constantly told they will need to use an external BEC for high torque servos in crawlers but yet try to prove everyone wrong.
If these "bends" made any difference, it should also affect the way suspension links worked. Hmmm...maybe THAT'S why the top guys have great handling rigs!!!!! Now I have to go get longer links and bend them like pretzels......sigh.....

These cranks "look nice" but I see no advantage other than to employ some people and make your wallet lighter.
This is like saying, "I have color coordinated hi "C" LiPO packs, you need to spend 4x the money to get my packs!" and people saddle up & buy them.

Oh, wait.......we already get that.....

Was it P. T. Barnum?, "There's a sucker born every day!"

PS, I like the typos in the company page. Not.

Last edited by Charlie-III; 10-04-2012 at 07:37 AM. Reason: Added suspension link reference....LOL
Charlie-III is offline   Reply With Quote
Old 10-04-2012, 07:34 AM   #8
Scale Detail Engineering
 
Join Date: Apr 2010
Location: Turtle Island
Posts: 5,573
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

ummm, I believe that's two 7's... not a Z. Dumbass!
johnnyh66 is offline   Reply With Quote
Old 10-04-2012, 07:50 AM   #9
I wanna be Dave
 
binaryterror's Avatar
 
Join Date: Jan 2004
Location: Detroit
Posts: 3,583
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Do people realize physics of a crank works point to point?

All this did was put a shape into the crank itself. The crank point is still mount to mount which is still a straight line.
binaryterror is offline   Reply With Quote
Old 10-04-2012, 08:26 AM   #10
I wanna be Dave
 
Join Date: Sep 2005
Location: Houston, TX
Posts: 16,952
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Quote:
Originally Posted by binaryterror View Post
Do people realize physics of a crank works point to point?

All this did was put a shape into the crank itself. The crank point is still mount to mount which is still a straight line.
Exactly.

Torque = Distance vector cross Force vector

You'd think with the word "torque" in the name of their product, they'd at least try to figure out what that means.

Last edited by JeremyH; 10-04-2012 at 08:28 AM.
JeremyH is offline   Reply With Quote
Old 10-04-2012, 08:34 AM   #11
I wanna be Dave
 
Join Date: Sep 2005
Location: Houston, TX
Posts: 16,952
Default

Quote:
Originally Posted by Hitman Cody2130 View Post
Looks like an interesting idea, would love to see the studies that they did as well as some strength tests compared to a straight crank
No need for further testing....didn't you see him try to break it by hand in the video? That proves it's strong!
JeremyH is offline   Reply With Quote
Old 10-04-2012, 08:37 AM   #12
Quarry Creeper
 
Join Date: Nov 2006
Location: DeSoto
Posts: 206
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Position Vector cross Force vector. I also believe we would need more than that. Position cross force gives the moment about a point; however, we want the torque about an axis. We would need the unit vector of the axis dot into the cross product of the position and force. This would give us the magnitude of the moment. Take magnitude of moment and multiply it by the unit vector of the axis for the Torque vector.

Or the answer could be waffles.


Quote:
Originally Posted by JeremyH View Post
Exactly.

Torque = Distance vector cross Force vector

You'd think with the word "torque" in the name of their product, they'd at least try to figure out what that means.
rnpnick is offline   Reply With Quote
Old 10-04-2012, 08:39 AM   #13
I wanna be Dave
 
binaryterror's Avatar
 
Join Date: Jan 2004
Location: Detroit
Posts: 3,583
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Quote:
Originally Posted by JeremyH View Post
Exactly.

Torque = Distance vector cross Force vector

You'd think with the word "torque" in the name of their product, they'd at least try to figure out what that means.
I've been trying to convince crawlers of this for years. Often I run offset rod ends or bent uppers. People think this changes the geometry, but all it does is change shape. The actual link is still rod end ball to rod end ball, bend the link to clear things. That does not effect the Eye-Eye measurement of the actual torque rod.

Shape doesn't equal physics.
binaryterror is offline   Reply With Quote
Old 10-04-2012, 08:42 AM   #14
I wanna be Dave
 
Join Date: Nov 2010
Location: 07456 N. NJ USofA
Posts: 8,314
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Quote:
Originally Posted by rnpnick View Post
Position Vector cross Force vector. I also believe we would need more than that. Position cross force gives the moment about a point; however, we want the torque about an axis. We would need the unit vector of the axis dot into the cross product of the position and force. This would give us the magnitude of the moment. Take magnitude of moment and multiply it by the unit vector of the axis for the Torque vector.

Or the answer could be waffles.
Nope....the answer would be "42".....

Oooopppsss.....wrong question.

As stated, the "design" looks cool but is worthless at a minimum, dangerous at the extreme.
Charlie-III is offline   Reply With Quote
Old 10-04-2012, 08:50 AM   #15
I wanna be Dave
 
Join Date: Sep 2005
Location: Houston, TX
Posts: 16,952
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Quote:
Originally Posted by rnpnick View Post
Position Vector cross Force vector. I also believe we would need more than that. Position cross force gives the moment about a point; however, we want the torque about an axis. We would need the unit vector of the axis dot into the cross product of the position and force. This would give us the magnitude of the moment. Take magnitude of moment and multiply it by the unit vector of the axis for the Torque vector.

Or the answer could be waffles.
What you are talking about is moment of inertia. The two topics are (obviously) somewhat related (t=MOI x angular acceleration). However, what these guys were saying is that their design has increased power output from the rider (which essentially means they increased torque output from the rider). The shape of this design has nothing to do with torque output because of that cross product in the torque formula. It eliminates all portions of the force applied that are not perpendicular to the displacement vector.

To increase the MOI, they would need to concentrate more of the mass of this crank toward the pedals....and even then it would only about double the MOI.

I really think they are just throwing out terms that they don't know and hoping people will buy it...

I like waffles.

Last edited by JeremyH; 10-04-2012 at 08:53 AM.
JeremyH is offline   Reply With Quote
Old 10-04-2012, 08:56 AM   #16
Rock Stacker
 
Join Date: Aug 2012
Location: Moreno Valley Ca
Posts: 52
Default

The angle must help with wind resistance, instead of a straight rod it now has a point which helps break through the on coming air.....:what:

For some reason I see a middle aged man trying to stand on his pedals coming down a hill only to have it break at the bend and well im sure we can all se where that goes....

Distance from a-b is just that doesn't matter what bends you put in between.

This is some funny chit. Some people....

Fat fingered from the phone- Corey
SunShine is offline   Reply With Quote
Old 10-04-2012, 08:59 AM   #17
Suck it up!
 
Duuuuuuuude's Avatar
 
Join Date: Mar 2008
Location: Arkansas
Posts: 11,652
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Duuuuuuuude is offline   Reply With Quote
Old 10-04-2012, 09:22 AM   #18
Quarry Creeper
 
Join Date: Nov 2006
Location: DeSoto
Posts: 206
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

Quote:
Originally Posted by JeremyH View Post
What you are talking about is moment of inertia. The two topics are (obviously) somewhat related (t=MOI x angular acceleration). However, what these guys were saying is that their design has increased power output from the rider (which essentially means they increased torque output from the rider). The shape of this design has nothing to do with torque output because of that cross product in the torque formula. It eliminates all portions of the force applied that are not perpendicular to the displacement vector.

To increase the MOI, they would need to concentrate more of the mass of this crank toward the pedals....and even then it would only about double the MOI.

I really think they are just throwing out terms that they don't know and hoping people will buy it...

I like waffles.
I agree, their design does not help.

I am not talking about moments of inertia. I am saying a moment of force that produces a turning effect or moment about a point. When I say moment it is interchangeable with torque. Moment in scalar form is simply Force times distance the same as torque. The process above holds true for finding torque about a specified axis.
rnpnick is offline   Reply With Quote
Old 10-04-2012, 09:33 AM   #19
RCC Addict
 
Join Date: Feb 2005
Location: Crawlifornia Uber Alles
Posts: 1,146
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

These garbage cranks are just like skateboards from the 80's that had weird shapes and cut outs. They called them 'money bumps' and 'money shapes'. It's just for morons that want to buy something that looks different, no matter how poorly they perform. And the square taper bottom bracket has gone the way of the dinosaur. So even if the cranks were normal, they are still fuct!
gregrocks90046 is offline   Reply With Quote
Old 10-04-2012, 09:44 AM   #20
Suck it up!
 
Duuuuuuuude's Avatar
 
Join Date: Mar 2008
Location: Arkansas
Posts: 11,652
Default Re: The Z Torque Bike Crank-Breaking Laws Of Physics

I'm not into bicycles in any way, shape, or form, but I keep thinking I've seen these or something like them before...
Duuuuuuuude is offline   Reply With Quote
Reply



The Z Torque Bike Crank-Breaking Laws Of Physics - Similar Threads
Thread Thread Starter Forum Replies Last Post
Crank 2 STANG KILLA SS Chit Chat 5 04-26-2009 08:13 PM
Physics game kinda like crawling! cheesefart Chit Chat 8 11-06-2008 10:11 AM
bored at the in-laws = new bike Cole82 Chit Chat 7 08-13-2007 07:53 PM
i guess this is a physics question roadblock Chit Chat 23 11-20-2006 12:20 PM
Attention Physics geeks...... Shock mount ? TwistedXT General Crawlers 17 01-28-2006 07:15 AM
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -6. The time now is 02:56 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Copyright 2004-2014 RCCrawler.com