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Old 04-08-24, 07:23 PM
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3alarmer
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Originally Posted by Jughed
Interesting perspective from an old rider, coach, team manager (manager of one Lance Armstrong) on why we are seeing so many major wrecks with more severe injuries.

-Stiffer frames
-stiffer wheels
-deep section wheels
-narrower bars
-angled brakes
-geometry that promotes riding on the hoods with arms bent vs in the drops.

The latest Vingo wreck - high speed, stiff unforgiving bike, probably the front wheel locked from a bouncing and disc brakes.

My point - this sport is really about the riders. If they were all on similar machines of any type, even old school steel - the racing would be the same.

...that link I gave, to bicycle aerodynamics considerations, mentions this, especially with regard to crosswinds and wheel rims.

The other main consideration when optimising the aerodynamic performance of equipment is the environmental conditions that will likely be encountered on the road or track. Road cyclists compete within a turbulent atmospheric boundary layer that exhibits gusty wind profiles that are rarely aligned with the direction of travel. Cross-winds result in flow asymmetries being generated around the bicycle and rider, as demonstrated in Fig. 9a, which not only affects the magnitude of the aerodynamic drag force but also generates additional side forces, rolling, and yaw moments. These forces and moments can result in a cyclist being unable to maintain control of their bicycle. Typically, aerodynamic styling to minimise drag is at odds with reducing aerodynamic side loads, rolling, and yaw moments and is why aerodynamic design to minimise these forces and moments is particularly important at the elite level. Gusty cross-wind conditions have resulted in a number of elite cyclists losing control during windy road racing events [67, 68]
Also, in the FWIW department:

​​​​​​​Although reducing wind resistance on the frame is important, it will always be limited as the majority of the wind resistance acts on the rider. Bicycles that have resulted in the largest gains in elite cycling performance have been achieved through designs that target the aerodynamics of rider position.
...

Compared to bicycle frame development of the early 90s, restrictions imposed by the UCI after 1996 have meant that aerodynamic improvements today are achieved through relatively minor modifications to a standard frame with aerodynamic tubing. Modern frames adhering to the “3:1 rule” are designed using both wind tunnel and CFD techniques with a focus on improving the aerodynamic interactions between the frame, front and rear wheels, and the rider.
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