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Old 08-16-24 | 08:40 AM
  #49  
tomato coupe
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Bikes: Colnago, Van Dessel, Factor, Cervelo, Ritchey

Originally Posted by choddo
Can just about read that. A higher quality image would have helped.
What’s the definition of the “effective radius” there? Cos based on the image alone it’s “distance from hub to an arbritrary dotted line”. Does PC=CA? And if so, why?
The diagram only shows the relationship between the radii -- it's not meant to be a means of determining the actual value of the effective radius.

Originally Posted by choddo
Ok I think I understand what tomato coupe is saying but I think he’s wrong for weights in bike territory as opposed to cars.
Auto tires are obviously designed to support higher loads than bicycle tires, but the same principle of effective radius under load applies to both.
Originally Posted by choddo
Figure 8.12 of this suggests the effective radius actually being smaller than the patch radius for weights below 1200N (about 120kilos)
https://www.sciencedirect.com/topics...rolling-radius
I don't see figure 8.12, but the first available figure in the link shows the same relationship between the unloaded, loaded, and effective radii as the diagram I posted.
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