FWIW current-gen Red cranks were near the bottom of the heap in terms of stiffness in Fairwheel’s test. That plus the dumb 1-piece PM/ring plus the crazy cost has always been a total turn-off to me. Running Force cranks even on bike w other Red components.
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Looks like a button on the front to control the head unit which would be nice. That is one of the things I like better about Di2 vs AXS
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Possible. But I bet not on Red because that would increase the weight a bit.
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Hood shape looks like it’s going back to 2008…Also, I hope the PM is completely incompatible with the old stuff so, I can add the AXS to the pile of other incompatible PM’s (Riken, Dzero and Cinqo) I have been unable to mix and match…
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I’m seriously debating this myself. Not sure if I can stomach mechanical though
Even though I am running Ultegra Di2 on my roadie, I still prefer the tactile feel of mechanical. My current gravel bike is GRX 11spd mech and I have zero complaints about it…and the tactile feel of Campag thumbshifters has always been a joy, so I have zero reservations about going Ekar.
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Yeah, I totally get that. I actually prefer the tactile sensation of electronic a lot more than mech. And really Shimano electronic in particular. My 9100 Di2 is a noticeably more precise feel than my SR 12 EPS.
I thought they did away with the thumb buttons on Ekar
No, that was on the new version of electronic Super Record…Ekar still has thumbshifters, but they are shaped a bit differently than the traditional “mouse ears”.
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if I’m interpreting their results correctly, there is like a <1MM difference in flexiness between the dub red cranks and the new shimano ones. what’s that mean in the real world outside of a testing rig?
Read the article. They estimate a couple-to-a-few watts lost to flex at ~300 watts, more at more watts.
I read the article when it was first mentioned on escape collective… I asked you about a clarification regarding the “real world” implications due to this (quoted from the article) -
"Remember, this assumes that no strain energy is returned to the drivetrain. "
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Also, is it possible that the force cranks you are running are even less stiff and more flexy than red cranks?
Lost watts are objectively as “real world” as it gets. One not caring about it doesn’t change physics.
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That’s why every grand tour was won on sram LOL. NO REPLIES… ITS JUST A JOKE
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Does your bike look like this tho? How many watts exactly is one losing when riding their bike in the real world?
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Why does it make a difference? Either it’s less stiff or it isn’t. You’re still making it go 'round. And if you accept it’s less stiff and the figures quoted, then you’re losing at least 2W at 300W. Now, you either care or you don’t. Most people don’t care about the lost watts and increased wear on a bad-lubed chain despite all the available evidence.
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Many thoughts come to mind…
I ride a bike, not a test rig.
Cranks are just one part of a system, and once there are multiple components and dynamics at play in a system, effects (especially when the differences are so small and unclear/within a margin of error) don’t necessarily stack up or play out in an intuitive or additive way.
Contextually, I have little idea of how big of an impact less than 1mm difference in flex makes. From the spectrum of infinitely stiff to infinitely flexy, the cranks compared seemed to all fall in a very small fraction of the total range.
There is no testable/proven info AFAIK that says a flexier crank = less power at the real point of importance (where the tire meets the ground/surface/track). If the difference was some much larger # of watts, I could understand the blind confidence in the idea that a flexier crank = less watts, but the difference is so small (fractions of watt), that in the bigger picture it is not certain.
There is a lot of weird stuff going on that remains to be unmeasured, atleast publicly AFAIK regarding chain bounce etc
I don’t think I understand your point. Are you suggesting there’s a possibility you’d recover the lost efficiency somehow?
Sounds like neither of you actually “read the article”:
Some of that spring-back energy probably helps turn the drivetrain while some of it may behave in a negative manner. However, there’s a fair amount of debate about how much energy is returned. The answer to the energy-return question involves kinematic analysis far outside the scope of this article. For now, we’ll assume that all of those 4.8 Watts spring back in a way that doesn’t help turn the drivetrain nor hinder it. As mentioned before, the most flexible crank in this review shows about 50% more deflection than the stiffest crank. Our FEA crank is quite flexible, and it absorbs 4.8 Watts of a 300-watt effort. Strain energy, roughly speaking, is inversely proportional to stiffness. We can use these relationships to calculate that at 300 Watts, our flexible crank absorbs 4.8 Watts, or 1.6% of total power output. Meanwhile, a 50% stiffer crank absorbs 3.2 Watts, or 1.07%, in strain energy (technically, strain power). That’s a difference of 1.6 Watts (or 4.7 watts at our tested 880 Watts).
Remember, this assumes that no strain energy is returned to the drivetrain. That’s not to say that crank stiffness is irrelevant, there is a measurable difference. It also provides all the psychological and “feel” benefits described at the beginning of this section. A stiff crank also incrementally improves efficiency by keeping bearings aligned, keeping the pedals more directly beneath your feet, etc. Keep in mind that this 1.6% calculated strain energy absorption represents an upper bound of energy dissipation—that is, the maximum possible energy loss due to crank flexure. Real cranks are much stiffer than our modeled crank and therefore store less strain energy. Moreover, a great deal of that stored strain energy is likely returned to the drivetrain. The real-world losses to crank flexure are, in all likelihood, a fraction of that number.
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