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WOW, I had a chance to put my hands on a set of these a few days ago, I WANT!! Look more like Art Work than a crankset, and LIGHT! The box they were in was heavier than the crankset, but damn that price!
 

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Ti isn't very stiff. Seems like a strange material to make cranks out of. But they are sexy.
 

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Aluminum is about half as stiff as titanium but has seemed to work ok for cranks.... Stiffness usually dominated by an items shape (size/diameter etc.)

These are so impractically expensive but I still want. Maybe if my current carbon cranks break? Something tells me these will be hard to find on the uaed market...
 

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I understood that ti had more give and flex in than aluminum. I stand corrected.
 

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Orange Bikes USA Dealer
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Here is some fun for you. Both pictures are of 170mm crank lengths so apples to apples.
Race Face Next SL G4 in comparison.

BTW, I sold the Race Face and they were new.
20181121_153718.jpg

20181110_145405.jpg
 

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I like the vibration dampening of my RF cranks vs XTR Aluminium they replaced. I would think the carbon would have better dampening than the Ti cranks.
 

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Orange Bikes USA Dealer
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I notice no vibration.

Just like a titanium hardtail rides better than an aluminum hardtail.
 

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I think I would wet my chamois with every pedal strike.
 
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Twice as stiff as Race Face Next R, and lighter too. Not too shabby. Check out this video: https://www.youtube.com/watch?v=yU0LNcYF734
Man I like the product. That video though...

Clearly engineers or physicists were not involved in the script. A flexible crank doesn't lose energy, it might suck to ride a really flexy crank but since a flexible crank is a spring the energy that goes into flex comes back out. The only loss would be energy lost as heat.

They should sell the thing on its (many) merits, not confused blather about the performance benefits of extreme stiffness.
 

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Man I like the product. That video though...

Clearly engineers or physicists were not involved in the script. A flexible crank doesn't lose energy, it might suck to ride a really flexy crank but since a flexible crank is a spring the energy that goes into flex comes back out. The only loss would be energy lost as heat.

They should sell the thing on its (many) merits, not confused blather about the performance benefits of extreme stiffness.
Except for in a carbon fiber crank, where flex indeed means lost energy. Buy mainly for higher frequencies than pedal frequency.

When it comes to axle flex, less is better, as it allows the bearings to be loaded correctly. I think this is where most of the stiffness of the EE Wings come from, a Ti axle will be twice as stiff as an alu axle of the same weight and diameter.
 

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Except for in a carbon fiber crank, where flex indeed means lost energy. Buy mainly for higher frequencies than pedal frequency.

When it comes to axle flex, less is better, as it allows the bearings to be loaded correctly. I think this is where most of the stiffness of the EE Wings come from, a Ti axle will be twice as stiff as an alu axle of the same weight and diameter.
You're technically right that there is some energy lost as heat, and an aluminum 30mm spindle is more flexible aluminum 30mm spindle, but those effects are way outside of any practical difference. Would you like to estimate the 'crank heating' that's reduced by using these cranks?

As for bearings... Would you compare stiffness of a flexy 30mm aluminum spindle against a classic steel square taper bb spindle? Again the flex damage delta is out at the lunatic fringe.


These cranks are light and tough and awesome - no need to sell with snake oil.
 

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You guys are killing the awesomeness of these cranks with your science!! lol. They're straight up sexy! I got an incredible bro deal from my lbs and bought some (had to - going on a ti frame). But I'll admit my first reaction on getting them out of the box was how light they are.
 

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Elitest thrill junkie
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Man I like the product. That video though...

Clearly engineers or physicists were not involved in the script. A flexible crank doesn't lose energy
That's not possible, the material would have to return 100% of the energy given to it, which doesn't happen. Crank flex is probably a minute player in a complex system of the spindle, bottom bracket, chain and seat stays, etc. If all of these and the crank arm are flexing significantly, you probably are losing out on some significant watts that could be propelling you forward.

Once we moved to large i-beam, C-section and hollow-forged cranks, I think most of the flexiness issues went away. The old sugino, way-old shimano and cook-bros type stuff was where you got a lot of flex in the cranks. Once we went to octalink 1 we boosted the spindle strength and stiffness significantly. It's only gotten better from there, but those were the biggest improvements IME stiffness-wise.
 

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..snip..

The old sugino, way-old shimano and cook-bros type stuff was where you got a lot of flex in the cranks.

..snip..

Here are my old Cook Brothers RSR cranks on my 1990 Fat Chance Yo Eddy with a Ti spindle. Flexy as a wet noodle but Super Cool!
 

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Here are my old Cook Brothers RSR cranks on my 1990 Fat Chance Yo Eddy with a Ti spindle. Flexy as a wet noodle but Super Cool!
Badass, I used to want a Yo Eddy so bad.
 

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That's not possible, the material would have to return 100% of the energy given to it, which doesn't happen. Crank flex is probably a minute player in a complex system of the spindle, bottom bracket, chain and seat stays, etc. If all of these and the crank arm are flexing significantly, you probably are losing out on some significant watts that could be propelling you forward.

Once we moved to large i-beam, C-section and hollow-forged cranks, I think most of the flexiness issues went away. The old sugino, way-old shimano and cook-bros type stuff was where you got a lot of flex in the cranks. Once we went to octalink 1 we boosted the spindle strength and stiffness significantly. It's only gotten better from there, but those were the biggest improvements IME stiffness-wise.
So yeah, I agree it isn't 100%. Even a steel leaf spring doesn't return 100%. But in both cases it is really darn close. Are you disagreeing about the magnitude of the heat loss? Or some biomechanical disadvantage of flex?

On all bikes with each pedal stroke you're loading a big spring - what doesn't go into forward goes into heat (very small number unless the metal starts to yield), and the rest comes back out as 'up' to the rider.

Long ago I did a long climb on a super noodly vitus road bike, the original bonded one from the 80s with the steel-sized tubes? Its flex was a problem because it was hard to keep going straight, silly flexy, but it was still fast up hill. The energy that went into flex wasn't being sucked away and wasted but you had to get your timing right, was easy to get discombobulated. Is not at all like a full suspension mtb where excess bobbing is damped by a shock, in that case the shock really is stealing energy by converting it to heat.

Ya I agree the old square taper spindles were the source of so much flex. I brought them up because in so many cases the bb bearings lasted a really long time even with all that flex. I love the new stiffness but it is a lie to claim huge significant efficiency gains.
 

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Badass, I used to want a Yo Eddy so bad.
I had those cranks on a klein I bought used. They were so sweet. I didn't mind the flex at all. Just looking down at them gave me power.

And the Yo Eddy. Ya. I used to go on short demo rides at the local shop whenever I could - they were sick of me. That bike felt so sweet but I just couldn't admit to myself that a heavy steel bike was worth all the money. They were so beautiful but so so expensive. Absolutely not affordable.
 
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