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New "Rotor Kit" Cranks(14 posts)

New "Rotor Kit" Cranksplasticol
Oct 24, 2001 12:29 AM
Does anybody knows anything about this Rotors from Spain that are supose to increase power by 15 %.

BWAHAHAHAHA!!! (nm)Rusty McNasty
Oct 24, 2001 2:50 AM
or: 15% more power my @$$!!! (nm)Rusty McNasty
Oct 24, 2001 11:42 AM
re: New "Rotor Kit" CranksDAC
Oct 24, 2001 6:09 AM
"Increase power by 15%"???
How, pray tell, do you accomplish this??
Do you mean "reduces drag by 15%", or possibly "weighs 15% less"?
You could increase TORQUE by making the cranks longer, but you can do that with any cranks.
Sounds like a load of hooey to me.
a few detailsDAC
Oct 26, 2001 5:50 AM
After reading the specifics on the Rotor site (the are in Spansh, only), It seems that these cranks weigh 240g more than a D/A crankset. Then it goes on to say that this increase in mass is acceptable, since it the performance increase will more than make up for it. How do you say 'hooey' en espanol? They also seem to think that the only reason Biopace chainrings failed was because of problems with front derailleur indexing. Que es mas hooey??
In all likelyhood, in a field where "weight weenies" argue about which rim tape is lighter, this invention doesn't stand a chance. I'm sure that it costs at best $250 for a crankset, and will break within a year.
Maybe they should aim it at the ATB crowd-they'll buy anything!!
re: What do they do? Change riders? nmdzrider
Oct 24, 2001 7:25 AM
Oct 25, 2001 10:32 AM
Before we all dismiss the idea here's a link on to a review at the bottom there is a link to the company.

Essentaily they're trying to make better use of the limitations of human ergonomics. One could entertain the possibility that moving the foot through a fixed and simple circle may not be the most efficient means in transmitting power to the drive train. This is essentially simple harmonic motion - one of the easiest things to understand and analyze - no reason why one should assume that it's simply the best.

It comes froma mechnical engineering department, so I'm sure they looked at the mechanics extensively, but the question of practicality needs to be addressed.

Ultimately efficiency is defined as the ratio between power out over power in.
Gee, nobody has ever thought of this before!Kerry Irons
Oct 26, 2001 5:11 AM
"Quack cranks" have been around since the invention of the safety bicycle in the late 1800s. Bent cranks, curved cranks, uneven length cranks, cam-activated cranks, super long cranks, super short cranks, "pedal action" cranks, and on and on, ad nauseum. They have, each and every one, claimed some sort of improved power output. They have, each and every one, proved to be impractical, ineffective, and just plain bad ideas. I'm sure however, that THIS one is different from all the rest, and is in fact a really good idea that works well and somehow causes the human body to deliver 15% more power with no more calorie consumption or demand on the physiological system. Yes sir! Because we'll believe anything.
there's a sucker born every minute!Rusty McNasty
Oct 26, 2001 5:37 AM
First question that comes to mind is:why would AERONAUTIC engineering students (in Spain, yet) be doing this? Perhaps they had some left-over aluminum stock, and nothing to do?
Second question: how much does the damn thing WEIGH?
Third: How much $$??
Fourth: How do you work on the damn thing?
Fifth: How does it affect your knees/feet.
Finnaly, the sixth, and most important question: WHY???
Oct 26, 2001 10:06 AM
All valid questions, but that has nothing to do with the original issue of a claimed increase in efficiency.

Fact of the matter is that aeronautical and mechanical engineering are very closely related - my dept. was actually called Mechanical & Aerospace Engineering. Before you even got into the upper division aero/mech electives you ahd to take all of the core mechanical courses. As to why - it would be pretty easy to imagine that they are working on a design competition for human powered flight and want to get every last bit of power out of the human and to the propeller. Nothing inherently wrong with engineers from Spain - afterall they were in the finals of the Americas Cup in San Diego, beating out the other challengers, as an example. A reasonable testement that they can design and build complex structures. At least their boat didn't break in half and sink like the Austrailians.

No one has said that this is the way cranks are going to go, that this is the future, or that it's even practical from a weight or economic stand point. Ultimately engineering is all about seeing what is out there and building a better mouse trap, but it can be a moot point if you don't have any mice to catch. Engineers like to tinker - it's part of our nature.

According to the US Patent Office, during there history, there have been more patents awarded for bicycle applications than any other field, yet one looks into it a bit and realizes that not many of them find their way to the market. many MTWB suspension designs that are in use today were actually patented back in the late 1800's.
if yer gonna bag us Aussies....crack-n-fail
Oct 27, 2001 5:14 PM
at least spell it (Australians)correctly, please!
Oh BTW, who finally beat the cheating, rule bending NYYC at Newport with a superior,revolutionary design that was expertly sailed back in the early/mid eighties?
Just yanking your chain, 'though with regards to the cranks, interesting, however the KISS principle usually comes out on top in my experience.
Oct 29, 2001 9:47 AM
Actually I've heard it was Austruckingfailians ;-) No doubt the Aussies are formidable watermen/women - I actually won a bet on the America's Cup back in the 80's by betting against the pompus NYYC (I'm from Boston - NY is oour big rival). Gotta remeber that Ben Lexan, the designer of the winged keel, wasn't Aussie - gasp - he was a Kiwi!

Gotta agree that the KISS Principle rules the day - but sometimes you need to develop a complex idea, then figure out how to make it simple and bomb-proof. Being open to new technology and then figuring out how to make it work well is the real art in engineering. We could still be riding on solid tires.....
Oct 29, 2001 10:37 AM
grzychimp apologizing? wonders never cease
Oct 29, 2001 11:21 AM
Yeah, well it was sort of backhanded and about as serious as the previous post.

It's more along the lines of saying, "I'm sorry you're so fat." ;-)