Spin Dancer wrote: No "maybe" about it - it is us.

As the kids say: Whatever...

Back to the regularly scheduled program:

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

Well, maybe you are right Frank, but at least I almost had you! Like I said, it just kind of popped into my head and made me laugh, so I thought I'd share. Glad you got the mask, think it's cool, and understand the place where some of my conjectures are transmitted from. Maybe the PC users who have difficulty adapting would find spinning on a trainer with the mask on helpful for quicker development.

Ha! Glad you liked the twist in names. It reminds me of Phil Liggett's comments of "dancing on the pedals"!

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

Rotor cranks don't help improve efficiency at all!! First of all, there is a 1993 article by Ed coyle down at the University of Texas that showed that pro cyclists pedal the exact same as recreational cyclists except they simply have more power. more specifically they push the pedal down with more force, they don't spin in a better circle they simply generate more power on the downstroke. During the upstroke all you try to do is unweight your foot. You don't try to generate force on the upstroke. Furthermore, cycling efficiency is around 18-22% depending on pedal rate and intensity. Even with rotor cranks you can't increase efficiency beyond that.

Cannon wrote: "Furthermore, cycling efficiency is around 18-22% depending on pedal rate and intensity. Even with rotor cranks you can't increase efficiency beyond that."

Sure you can, if you have the right traiing tools. At least theorectically as the efficiency of cyclists is about 50% of the efficiency of the contracting muscle. Part of the benefits of the PowerCranks is improving the efficiency of the cyclist (do a search for the Lutrell study here). The Coyle study was done in the pre PC era. The only question yet to be answered is how much efficiency can be gained. I also believe RC's can increase efficiency some also, although i believe it is not as great as the improvements possible with PC's.

Frank

---

--------------
Frank,
An original Ironman and the Inventor of PowerCranks

cannon,

You can read all the published benefits on the Rotorcranks.com web site.

Specifically they have been proven to improve performance by lowering lactate levels 13-17%, lowering heart rates for the same wattage output, raising lactate threshold, and reducing knee pain.


Gary Tingley

RotorCranksUSA.com

[reply]
Cannon wrote: "Furthermore, cycling efficiency is around 18-22% depending on pedal rate and intensity. Even with rotor cranks you can't increase efficiency beyond that."

Sure you can, if you have the right traiing tools. At least theorectically as the efficiency of cyclists is about 50% of the efficiency of the contracting muscle. Part of the benefits of the PowerCranks is improving the efficiency of the cyclist (do a search for the Lutrell study here). The Coyle study was done in the pre PC era. The only question yet to be answered is how much efficiency can be gained. I also believe RC's can increase efficiency some also, although i believe it is not as great as the improvements possible with PC's.

Frank
=====================================

Most power is required when riding TT's, and during
TT's most of today's Pro riders are sitting in a forward
position on the tips of their saddles. This is not a
suitable position for circular pedaling especially where
pulling back and up is concerned, so this would seem
to eliminate any advantage that PC's have to offer
during TT's. Not so with RC's as they can be used
equally successfully in a forward or backward position
with normal pedaling styles.

Okay...thanks to everyone for all the comments posted. Much appreciated.

I came to a conclusion. I am ROTORIZING!!!!

I have ordered a RS4X road double set with 52-39 chainrings. I will comment on what I think of it all as soon as I get some km's done with them both on the indoor trainer and the road.

I also have a PowerTap SL hub coming to me as soon as its released so it will be interesting to see how many watts I can pull with it compared with the normal cranks....

yes yes yes you need accurate set-ups to carry out the tests etc etc but tell you what....if you can get from A to B noticeably faster, and I feel my pedalling is more efficient and to boot I'm less tired, then hey they're good enough for me!!!!!!

---

Stephen Perera
Gibraltar, Europe
graphics@gibraltar.gi

sperera wrote: I came to a conclusion. I am ROTORIZING!!!

Good idea. Just get them installed correctly, as per the instructions. I prefered to do it myself, because I knew I'd follow the directions...not all bike mechanics are so inclined...so be selective if you have someone else do it for you. See what they do for you. Don't be surprised if you find you can use a larger chainring. I have a extra 53 that fits Rotors if you are interested (I found I can actually effectively use a 54X11 when on Rotors if I have ANY tailwind on a flat, or on any downhill, unless the downhill is so steep that it's better to just coast). If you don't see a measurable, noticible improvement in speed at a given effort, you have 30 days to send them back. Welcome to the individual experimental side of bicycling...I think it's fun over here!

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

The new 2005 model is very easy to install, it has splined crankarms.

Gary wrote: The new 2005 model is very easy to install, it has splined crankarms.

I didn't have a problem installing last year's model, but, I look forward to installing the 2005 model when it arrives by FedEx tomorrow!

In the meanwhile, I've been riding one bike with regular cranks for over a week now, and my muscles ached in a way that tells me I'm doing something they're not used to doing. This causes me to consider if periodically doing so is not a bad idea.

Stick with me just a second and think about it. Rotor Cranks have certain pedalling characteristics that are slightly different than regular cranks. When first riding Rotor Cranks, your quads tend to get tired in a little different way. I experienced a similar "tired" feeling when going back to regular cranks for a bit. Maybe there is a good training reason to cross-train with these slight differences. After all, we train slightly above LT and slightly below LT as well as right on LT, or do hill climbs when preparing for a flat course, or do high speed flat course training when preparing for a hill climb, or doing lunges as a leg workout instead of 100% riding, etc.

Another way to look at it is this: Would training on Rotor Cranks benefit riding while on regular cranks? IF the rider is getting a benefit from muscular adaptation to the slowing of the crank in the power phase, would that adaptation show up as performing better on regular cranks? Similarly, since regular cranks don't allow the cranks to speed up/slow down, would training on regular cranks produce muscular adaptation not stimulated so much while riding on Rotor Cranks, so that some regular crank training would improve your Rotor Crank riding?

I'm getting this idea partly from something JustCurious said, maybe a year ago, about PowerCranks. JustCurious opined that perhaps there is a beneficial training effect to PowerCranks, even if PowerCranks weren't faster, nor a better pedalling strategy than regular cranks. The point is not to argue about that statement, the point is to consider potential beneficial training effects. Put that idea together with feeling some unusual tiredness in my legs from being on a regular crank for 100 miles (not done all at once), and I just wondered if it might be beneficial to do this periodically.

I'm slower on regular cranks, no doubt in my mind. I was immediately faster on Rotor Cranks from my very first ride (which wasn't a long ride...maybe 25 miles best I remember). But, it took a while (couple of months) before the "differently tired" feeling went away when on Rotor Cranks.

I know, in real world courses, I'm faster on Rotor Cranks. Still, I plan on doing a "test" tomorrow on a trainer, using cadence, HR, and distance, to see if there is a discernable difference in performance on two identically set up bikes, except one with Rotors, one with regular cranks. I'll go back and forth on each bike several times. I could throw my PowerCrank bike into the mix, but, it's set up like a road bike. In the end, this test won't mean anything from a scientific point of view, this would have to be done with a much bigger sample size, perhaps even literally obstructing the vision of the cranks from the rider! But, I'm interested in what difference, if any, may be noted in my performance on the two cranksets in my garage on my trainer.

I'll post the results, even if they show no difference, sometime tomorrow.

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

actually, all this makes me think....I'm getting my Rotors tomorrow and may have them installed for Sundays ride on the roads....now, I have a hill climb TT 2 weeks from now....should I use the normal cranks leading up to the TT and then afterwards install the Roros or go Rotors from day one?

---

Stephen Perera
Gibraltar, Europe
graphics@gibraltar.gi

Being a hill climb TT I think you could use the Rotors, IF you get enough time on them to adapt - so ride them as much as possible for the next two weeks.

yes, I can't resist not riding them anyway...hey, get Ramon in Madrid to send them to me asap!!!!!! he said he was going to send them out today to get to me tomorrow...

I already have the bike shop ready to stick them on before the weekend...if it gets here tomorrow!

As I said, I'm getting the RS4X road double....I will leave them on the no.3 setting you recomend yes?

By the way, I've seen crank stiffness tests out there...have they been tested for stiffness compared to the Dura Ace 2004 and the Cannondale Hollowgram cranks for example.....all much of a muchness anyway though.....for normal riders like me.....

By the way, I really like the black chainmrings instead of the silver (metal) colour) normal ones on other cranks!

---

Stephen Perera
Gibraltar, Europe
graphics@gibraltar.gi

Rotor Cranks are visibly stiffer than Dura Ace.

I can rub the Dura Ace chainrings much easier than the Rotors. I can easily see the Dura Ace chainrings wobble back and forth in the front derailleur as I pedal, even when not pedalling hard. The Rotors don't wobble as much when pedalling as hard as I can compared to the Dura Ace wobble at normal pedal pressure. Now these are not the newest Dura Ace...I think the newest Dura Ace has adopted a bottom bracket more similar to the Rotor style, so maybe the newest Dura Ace is stiffer than the previous model.

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

OK, first ever Rotor Crank vs. Regular crankset on identically positioned bikes for me. 175 cm cranklengths on each, on a fluid resistance trainer, used the same rear wheel and same wireless computer, just swapped it over and taped the sensor in place on the chainstay with masking tape.

Using 42/14 gear:

speed on Rotors: 18.5 mph at rpms 85, HR 153.

regular cranks: speed 18.3-18.4 at 83 rpms, HR 157.

I swapped back and forth so each bike had 3 sessions about 5 minutes long. Kept getting these same numbers. I chose this gear because it felt about right for a racing effort in a half IM. Not much difference in the numbers between the cranks, but, I think it demonstrates the tendency that I suspected in my riding. I find I always tend to run higher rpms on the Rotors (just the opposite of what I hear many Rotor riders say)...I would have liked to have run higher rpms than I did on the Rotors, but, I was trying to keep the same rpms that I usually used on regular cranks, and hit the HR where I like to race...which is under 160. FWIW.

Edit: Hmm, after doing some calculations, I see my new wireless computer is off a bit...I was actually going just a bit faster than the readout. I wondered if I had lost that much fitness in my post IM break, because I usually am going faster than that at those HRs. No matter, that's one of the reasons I used the same computer and wheel on both bikes.

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

For me, hill climb tests have always been a better means of measuring the benefits of the system. Remember that you are fully adapted, and in our experience, adapted riders can carry the muscular improvements from the Rotors over to conventional cranks.

The test does not take into account lactic acid production, did you ride anywhere near LT? (Just wondering)

I did a CP 30 test today on the trainer, and noticed that is is much more difficult to perform on the trainer than on the road, likely due to the heat and focus. I did get my HR up there, a bit over LT, 176-178 for the last 10 mins, which is about 2-4 beats higher than most time trials I did last season.

My avg wattage was 295 for the CP30.

Gary wrote: adapted riders can carry the muscular improvements from the Rotors over to conventional cranks.

That was what I was wondering aloud in an earlier post. It seems to me that this would be true.

As far as my little test, using a computrainer would be a very good way to do this test. I don't have one. You could even blind yourself to the numbers as you did the test. Simply hit a certain rpm and HR, don't look at your gearing or wattage, and after you do the test, look at the saved graphs to see if there is a noticeable difference in watts at the same rpm and HR.

I don't really know my LT, but, my max HR is about 178. 85% of that is low 150's, so the HR range I used seems about right. Something I didn't mention was the whirring noise on the trainer...it is smoother when I'm on Rotors. Not something I could include in test results, because it is so subjective. A hillclimb would have been nice to compare, too. It was raining yesterday, though. I just wanted to run a quick and available test before taking the regular cranks off the bike that has them, and replacing them with Rotor Cranks later today....looking forward to that!

One more thing. I am still amazed at the greater stiffness in the Rotors. The regular crank bike had the previous model Dura Ace cranks on an Ultegra bottom bracket. There is an obvious difference in the chainring's movement side-to-side in the front derailleur, even pedalling at this normal effort level. Maybe the newer Dura Ace cranks are stiffer, I don't know...my front derailleur stiffness test isn't scientific...but, it sure is obvious.

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)

We are going to be testing the system using Computrainers in the near future.

One of these would serve to measure sound pressure variances.

Joe, you sure do have access to a lot of neat stuff!

---

Quid quid latine dictum sit altum videtur
(That which is said in Latin sounds profound)