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The internet seems to disagree with that:
http://www.reddit.com/r/Velo/comments/29oedw/the_case_against_rotating_weight/
https://van.physics.illinois.edu/qa/listing.php?id=7559
Yes, the wheel weight counts more than the frame weight. The reaon is that when you accelerate the bike everything moves forward together but the wheels also rotate. The average velocity over the whole wheel is the same as the rest of the bike, because the different parts move all the different directions in a circle. however, energy goes as the square of the velocity, and the rotational energy of the wheel just adds to the energy of the average motion. So you have to pump more energy into the bike to get a pound of wheel moving than to get a pound of frame moving. If all the weight of the wheel were out at the rim (which isn’t too far from true) the total wheel energy per pound would be twice the frame energy per pound, i.e. equal rotational and static weight. The real rotational number would be a little less.
Of course if you’re going uphill, the extra work to lift the bike against gravity only depends on the ordinary weight, not how it’s distributed. -
No it doesnt
Obviously gravity doesnt give a shit where the weight is. Thats not my argument. My argument is that the Wheel weight has more effect when accelerating (which that article agrees With), and that as you lose momentum faster up hill. You effectivly need to accelerate more going uphill (which that article doesnt mention. But try rolling a ball uphill. I'm not lying here).
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...still nearly a full day left to argue over the aero gains of deep profile Wheels in a Group start race........
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An offical should have stepped out in front of him and demanded he stop and pick it up.
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Intuitively (and I'm more than willing to concede I'm wrong here) I don't think you accelerate more going uphill, as acceleration is defined as the rate of change in velocity.
I don't think I'm speeding up and slowing down with each pedal stroke when climbing.
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I'm sorry but am I the only that saw Aru practically sat in the team car going up the Mortirolo at one point?
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Well on a hard Climb I lose speed every deadspot of my pedal stroke, and gain it again as I go through the Power spot. The steeper the hill, the faster I will lose speed, and thus the more accelerating I will need to do.
I'm kinda interested if the pros are so much smoother in there pedalling to drastically reduce this effect.
...But I dont think anyone else is. Maybe we should drop it ;)
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Dropped! Like [insert cyclist here] on [famous climb type #45].
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Had a very strong start to the season, got ill before.. was it Tirreno Adriatico? Dropped out of that, then rode Tour de Romandie and did ok, not riding at his best yet. Assume he's doing the Dauphiné as his build up to the TdF?
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Anything interesting happen? I've been client-ing all afternoon.
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Did you just quote reddit for #pubscience?
Mid 90s pro bikes were around 8kg I think. Frames were certainly less stiff. Wheels were light or aero (not both). All the best engines had turbos.
Reduced rotating mass helps you jump onto someone's wheel on a climb a bit at lower speeds. They help people going very slowly on climbs I guess but that's not often applicable for the pros.
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Pro-cycling thread
Posted by
@dancing james
When you're climbing a steep hill you have very little momentum. Which is why it feels very different to the same Power output on the flat. So you constantly accelerate Your Wheels.
Seeing the pros use very low profil Wheels, on mountain stages, when their bikes are struggling to make the legal weight With semi deep rims. Is a good indication of this.