Disc wheels road races

Road racing is very much a different discipline than time trialing. The minimal aero gains of a disc over a deep dish wheel are well offset by the weight and the loss of handling.

That, and it's not permitted.

Edited by ziggie204 2017-02-08 7:54 PM

Well, let me ask.
What is the advantage of a disk wheel? I can't see how it would help anything? I admit I don't know anything about this, but I live in an area that is flat and windy almost always. To me, it seems like it would be a nightmare in a cross wind??
Thanks for any education on this!

Think of a spoke slicing through air as it rotates around the hub. No matter how thin, it creates a little bit of drag, right? Now multiply that by the number of spokes in a rear wheel, usually at least 20. 20 x a little bit = not insignificant drag. Shouldn't be too hard to imagine why covering or replacing the spokes with a smooth surface results in measurably less drag.

And, at certain apparent wind angles, the large surface of a disc wheel can sometimes act like a sail, providing a modest amount of forward thrust.

Edited by gary p 2017-02-09 11:26 AM

For a few reasons... first disc wheels are banned in mass start events, for good reasons. When you're by yourself, a few inches push from side to side is not a big deal, in peloton, a few inches could mean a mass crash. Second reason is weight and rotational weight, a disc tend to be a bit heavier than a typical deep dish wheel which plays a role uphill, rotational weight matters when it comes to acceleration, which you do a lot in a peloton (pull, sit back, pull again, etc. or accelerate out of corner due the "rubber band effect").

Disc wheels do offer quite a bit of an advantage in non-mass start (or non draft legal) events as you get a more even flow and release of air. Difference between a deep dish and a disc wheel can be ~20-30 seconds in an Oly (which doesn't matter much if your goal is to finish, but it does matter if fight for a podium).