Dead point is the void at 12 and 6 o'clock, which you have with all traditional cranks, including fixed cranks

Rotor has no 12 and 6 alignment, eliminating the void

This may sound stupid so forgive me if I missed something. Why even spend money on a fixed gear bike? Just put your bike in a gear and do not shift for the whole ride?

I think he means like a track bike with no free wheeling <the gear is fixed to wheel hub > pure bike , No click - click coasting , your legs are along for the ride.

Thanks for the clarification. Feel kind of dumb now......Not new,I am married,wife does it to me all the time.

Though,still,could you not get "most" of the benifits of a fixed gear by just "deciding to go for a ride in one gear(and at least try not to coast,might of make it more of a mental challenge?)

I think there's a lot of ways to improve your cadence and pedal motion including equipment and drills. One legged drills, various cranks, probably even just training rides where you consciously think about a good fluid motion.

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Slowguy

(insert pithy phrase here...)

Pluto...let's see, that's near Uranus, right?

Sorry, couldn't avoid the cheap-shot joke, but, it's just a joke!

Fixed gear essentially increases the inertia of the drivetrain, enough so, that it can actually force your foot over the top. But, if fixed gear were better than deraileurs, there would be more riders on fixed gear in races.

I don't particularly like the term "eliminate" when talking about Rotorcranks and the "dead spot". I prefer to say Rotorcranks "potentially minimize the effect of the reduced power area in the pedal arc corresponding to the 12:00 and 6:00 positions". If you don't push slightly earlier, getting that crankarm over the top sooner is of no benefit in minimizing the reduced power area. However, it seems very easy to learn to do.

What I DO think contributes to making Rotorcranks work has at least something to do with slowing the crank/leg on the downstroke in the (I assume) more biomechanically powerful area somewhere between 2:00 and 5:00. This slowing increases economy, as suggested by a recent study inversely linking the speed of the foot with economy, i.e., the slower the foot is moving, the more economical. (Of course, there are limits to this economy, and at some point, progessively lower rpms aren't sustainable nor practical in a cycling model.) Another way to put it is, slightly slowing the footspeed gets more power to the wheel at the same energy expenditure.

Another thing may be that the hamstrings, although not as powerful as the quads, are able to move the lower leg quickly due to being a two-joint muscle system. Since the pedal is moving most quickly on the upstroke, this plays into the biomechanical "sweet spot" function of the hamstrings...moving the lower leg quickly upwards is what they do best.

Put both of these biomechanical "sweet spots" together: the quads being able to contract against a slightly slower foot movement, and the hamstrings moving the lower leg upward quickly, and maybe Rotorcranks work somewhat because of these reasons.

All the mumbo-jumbo theory and terminology aside, you just have ride them to believe it. It's much like having one more cog in the rear cluster...if you usually ride in a 53x16 on a particular stretch of road, you will find yourself riding in a 53x15 at the same level of effort. That's proof enough for me.

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

When talking about Rotorcranks and the "dead spot"

This must only work on flat ground high cadence pedal style, I can see problems in slow pedaling off the seat , pulling your feet up ,on the back half of the circle ? which makes the dead spot 90 degrees out.

Helitech, I think one thing that confuses people about Rotorcranks is trying to imagine the crankarms slowing down and speeding up. But, it's very subtle. I can't feel the crankarm slow down or speed up. It doesn't matter if I'm at low or high rpms, (although it just occured to me that I've never tried to see what my maximum rpms are on Rotors compared to regular cranks...I guess because maximum rpms aren't important to someone doing triathlons!). As far as climbing out of the saddle...I usually don't do it...but, when I do, I find it's easier on Rotorcranks than regular cranks.

Another thing I will say, I thought I was adapted to them in just a couple of rides. But, I was only faster on gentle-sloping terrain, not better on steep hills. Looking back, I know it was because I had not yet adapted. So, there must be some reason(s) for the adaptation period...meaning that your muscles are experiencing a difference, even if your proprioceptors don't feel a significant difference between regular and Rotorcranks. My quads seemed more tired on the run for a few weeks, so I was concerned my run times would suffer. Didn't happen...that was a relief! I'm not running faster, though.

I know none of this information really matters. It's just my attempt to explain it how I see it.

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

There must be some friction /drag on the crank arm or mechanical cam, as I can't see how a free swinging arm for 15 deg. would be rideable.

There is some very slight friction due to the pivots, but taken as a whole, the benefits of the system outweight the friction.

You are correct, it is not a free swinging arm. There is a slight stiction probably in the pivot points, but, I was surprised at how smooth it is in real life. Another thing that really impressed me is that the big chainring has less deflection left and right as I pedal, compared to my Ultegra and Dura-Ace cranksets. So, I don't have to fine-tune the front derailleur as much. These things are stiff!

Let me sum up what a fellow historically closely-matched competitor said to me in a race where I leap-frogged ahead of him on the bike course: "What did you do, quit your day job?" They made enough of a difference in speed for me that a competitor recognized it...until this year, he would always beat me on the bike split. Not this year. Our respective swim and run time differences have remained unchanged.

Nothing read in anecdotal reports would convince a scientist that Rotorcranks work. And I'm not trying to convince you that they work. It's pointless, and fruitless. I'll be glad to discuss what seems to be happening with me and my experiences with them, but, don't feel like I'm trying to convince you to get them. I have an unusual way of training (compared to the generally accepted ubiquitous exercise programs for triathletes on the internet and in magazines) both in types of exercises done as well as duration, and all I care is that I get results. I could be exercising in a manner that has heretofore been undiscovered, and I should make it known to the world...OR (I think more likely), there is something beneficial about a year and a half of PowerCrank training combined with a couple of months of Rotorcrank training/racing.

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