This is very different from Biopace because completely eliminates the lack of power that is exerted when the crank is in the vertical position and it is compatible with all front indexed shifting systems.
in theory, would slow the downstroke AND upstroke and increase the speed across the top and bottom. Quite different in concept and degree.
I thought that is what the rotor cranks do also. Don’t the make the pedal pass very quickly through the dead spots at top & bottom so you can spend more time in the down stroke?
Maybe you should take another trip to the web site Gary. I think that is what I say, if I don’t, please let me know where and I will change it.
I have no idea what someone can get using them less than all the time. They should get better but it is clear to me that it is much less than they get if they use them all the time. I really don’t care because i am primarily interested in exploring the FULL potential, not partial potential for the lazy. I advertise them as serious devices for the serious athlete, not instant speed.
No, they push the foot up faster on the backside. At least that is my understanding. the real “dead spot” in everyones stroke, except it is much more than a spot.
Maybe you should take another trip to the web site Gary. I think that is what I say, if I don’t, please let me know where and I will change it.
I have no idea what someone can get using them less than all the time. They should get better but it is clear to me that it is much less than they get if they use them all the time. I really don’t care because i am primarily interested in exploring the FULL potential, not partial potential for the lazy. I advertise them as serious devices for the serious athlete, not instant speed.
Wow, so athletes who do not incorporate PowerCranks useage into 100% of their riding are lazy in your view?
Thats too bad, I’m sorry you feel that way about all the lazy cyclists out there. Thanks for voicing your opinion. Im sure Coach Gordo, Dr Coggan and L. Zinn will pass this along to all the lazy cyclists they come across.
Anyway, another lazy triathlete, some guy named Chris McCormack, says about his PowerCranks that “I ride 100 miles per week on them and another 200-250 miles on normal cranks.”
The dead spot area covers 11 to 1 o’clock and rotor enables you to
partially compensate for the 12 to 1 o’clock portion, partially because
you have to apply some of the extra power in an area where maximum
power cannot be applied, that is between 1 and 2 o’clock and you will
also have to cope with three different pedal speeds in each pedal revolution. Let’s suppose by doubling the equipment, we were to double
the advantage by having the top pedal at 1 o’clock when lower
pedal was only at 5 o’clock, with only two pedal speeds to cope with,
you now would feel confident in claiming that you had totally eliminated
the dead spot area. In reality you have partially compensated for all
of that area and in addition, with the round pedaling style, you will
always have a slight pause in power application as you switch power
application from one leg to the other. Of course with all that extra
friction in equipment, its weight and possibility of breakdown, you have
added disadvantages that do not exist with normal pedaling.
It is amazing what trouble people will go to in order to try and eliminate
a problem that was successfully eliminated over half a century ago,
but those who called themselves experts did not have the brains to
figure it out.
Now I see the difference.
I accept that others have a different view as to how to best utilize them. Most of them who are doing it that way have told me they have found them “too hard” to do all their riding on them. Whether that is laziness or something else (ego perhaps) i don’t know. I accept they are trying to maximize their race results and working very hard to that end.
I have my bias as to what is the best way to use them. When the PC’s have become generally accepted (or if there is data to suggest otherwise) then i will explore whether some of these other techniques are better than my own ideas. I have enough athletes to look at and it seems that my data suggests that the more they are being used the better the results. SL used them a lot in 2001 (exclusively for about 4 months) and has dropped off since. Jo Lawn uses them more (and longer) than Lisa Bentley has. Unknown cyclist Todd Herriott uses them exclusively for one year and wins tour of cuba this year.
I see pretty much everything that is going on with them. I am not wedded to anything other than trying to find out what works best for them for most people. My data (over 4 years) suggests exclusive use is the best way to train with them. We should find out this year if racing with them offers any benefit as I think it will if one has enough time on them.
Frank
Frank / Gary,
Can I suggest that you two ignore each other? I don’t know the whole story but it is obvious that there is some bad blood here.
Frank - there is more than enough positive PC stuff on this forum such that when Gary slams PCs we all see the other side - even without you defending it. Everyone that has been here for a while knows that Gary has it in for PCs.
Gary - I thought you were leaving? Leave PCs alone. If you want to talk about your new discovery great. But do it without putting down another product. As my mother says be constructive not destructive.
This is the only forum on the web that I watch or participate in. Why? Because it is civilized, supportive and informative. I prefer discussions that are more intellectual. The whole discussion about Allison’s collumn is strong proof of that.
I find that when the two of you get together it makes for a negative unproductive discussion although I think that independent of each other you are both valuable contributors.
I am sorry, I only had the abstract and think I ought to see the entire study before I comment more. If this is an average pedal velocity it is worthless because it doesn’t go to pedal velocity when power is applied. If it is minimal or maximal downstroke pedal velocity it doesn’t seem to make any sense to me based on the abstract.
Where can i get the paper?
Frank
then this discussion has come to a screeching halt.
…and then, two months later, it re-emerged.
In the very first note on this thread, a review I sent in to cyclingnews.com was cited and inserted. In it, I said "if it ever stops snowing here, I hope to validate all this on the road fairly soon (my first TT is April 5)."
Here’s the proised-but-as-yet-undelivered update. Bottom line is that the first race on the Rotor cranks went very, very well. I finished 2nd overall out of 180 racers (and first non-pro), and set a new age group record for the course http://www.truesport.com/Bike/2003/results/sandytt.html
Given that the race was won by my friend (neo-pro) Gui Nellessen, who is 31 years (sic) younger than I am, I ''d have to say I was pretty pleased with that result.
PS: Some folks will know Gui as a member of the US national junior track team – his group set the US record at the world’s in the 4 km pursuit.
best, Richard Burkholder
wow, thats a huge accomplishment, congrats,
some questions:
-
what’s the warranty on those cranks?
-
do you notice and/or feel any resistance in the gearing in the cranks?
-
is it difficult to get accustomed to the rotors when switching to other cranks?
thanks, Gary
Quick PS: official results by category are at http://users.tellurian.net/jeanp/njba/, under April 5 (results). Major point is that yes, they really do seem to “work” – at least in this 7 mile event (similar to a tour prologue)…
Unfortunately, your improvement, as proof of the efficaacy of these cranks, suffers from the same defect as the improvements reported by PC users, it is purely anecdotal.
The concept of Rotor Cranks makes sense to me and I can see how they could help, although i think, taken alone, they have less potential than PC’s. However, I also believe they could be additive to the PC benefits.
The fellow who evaluated the RC’s for Cyclingnews.com is now currently evaluating the PC’s (I elicited the exclusive use promise from him) and, in our back and forth before he started I mentioned that after he was through with the PC test that he then, again, look at the RC’s to see if there is any potential additional benefit.
RC’s have a similar credibility problem as do the PC’s amongst the academics. At least PC’s are starting to make inroads. There is a new edition of Bicycling Science (Whitt and Wilson) coming out (so I am told) and PC’s are going to be included. I was talking with the person doing this section trying to put him in touch with others who might have some real data on the PC’s and mentioned RotorCranks to him - thinking they should be included in the section also, if it were not too late. He knew about them but thought it was something like biopace revisited. They won’t even be mentioned it looks like. Too bad if they really work.
Frank
There’s a motto in the SEALs: “equip the man, not man the equipment"
I think that this is one of the major differences between the cranks.
Hi Gary (think I know you from Cobb’s site. eh?)
I’m embarrassed to say I’ll have to go look up the warrantee info – you might find some of that online at http://www.rotorbike.com/eng/index.html , though you might have to switch to the Spanish language version (this is a very small company based outside of Madrid – set up by a former aerospace engineer who had a brainstorm while contemplating how the dead spot in the pedaling cycle might be addressed).
Now to the stuff I *can *answer…
The honest truth is that I noticed almost no difference at all – though those withy a “purer” pedal stroke (spinners) no doubt will at first. I tend more toward the big gear ‘masher’ style – so perhaps the reason I noticed so little difference is that my stroke ain’t all that circular to start with.
What is really way cool about the system is that the cam only comes into play in accelerating the trailing pedal through the dead 1:30pm to 10:30am spot – there is a little video on there website that shows this graphically better than I can describe it.
Subjectively, the workmanship looks superb – my bike techie (who is both very experienced and a bit of a Luddite about any new stuff) was blown away by its simplicity, lack of internal friction and evident machining quality.
I opted for the titanium version in 180 mm length – same length as on my prior setup. And I’ve stomped on them like crazy, doing 4km tests, flat out sprints, and even “killermeters” (1km).
Not sure how they would work for climbing – and frankly, I don’t care. Our TT’s here are near-flat, and I long ago took the second front derailleur off my Cervelo P3 and filed doen the mount boss for it. 
“How much do they run?”
The listed price on the website is 530 Euros, or about $ 600.
Sorry 'bout the typos and misspellings (rushing, 'cause I’m at work).
The video showing how the cammed setup works is at http://www.rotorbike.com/eng/htVideo.html – it takes a while to load.
Their site is a bit rudimentary and slow – and there’s more on the Spanish part of it than on the main English language link. As I said, they’re still a very small company, set up by a few brainstormers (sort of like Cervelo was not too long ago).
Kind of the unconventional, Graham Obree-style, “build a (faster) mousetrap” approach.