DIsc VS Disc Cover

A wheel cover is a heck of a lot cheaper than a true disc wheel.  I assume that a true disc will be more aero, but it's up to if that's worth $hundreds more.  I assume most people that use disc covers keep them on all the time.

There is at least one pro triathlete who ran an 808 with a disc cover rather than a disc.  They had tested it in the wind tunnel and found that the disc cover on the 808 was faster than the disc (which has led to both Hed and Zipp making discs that are basically covered 808s).

I have a cover on my 50mm tubulars and it lives on my wheel - if I ever do a race where discs aren't permitted I will take it off but for now, if I'm racing, it is with the disc cover.

Shane

I own a disc and a deep (100mm) rear. I typically ride the disc. I have a cover for the rear wheel, and have raced it as well as raced just the bare deep rear. I really don't notice much difference in speed or performance. Where I do notice the difference is when cross winds are high, my bike is more stable on the rear disc (or wheel/cover) - I thought it would be the opposite - so I will be running the disc full time.

Again, I did not notice any difference between the disc or the wheel/cover combination - they were both very fast - though the disc, at 960g is alot lighter than the wheel/cover 995g for wheel, 300g cover.

This is a key point that bears repeating - although many think that a disc will be hard to control in windy conditions, a disc (or cover) moves the centre of pressure of the bike back and improves stability rather than reducing it.



However, that 335g is about the equivalent of a 12oz water bottle and for almost all tri/TT applications, weight can be ignored anyway.

Shane

But with the cover you don't get that sweet "whoosh whoosh" sound as you ride...


I've got a set of 404's with a rear cover from wheelbuilder... great investment.