Road Cycling - Drag ?

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ArcSpin
07-23-02, 02:09 PM
Hi all!

Ok! here's a question that me and my cycling buddy didn't have and answer too and now I'm hoping to find a good answer to it here.

I have a pair of regular wheels (SPINNERGY X-AERO LIGHT).

How much do I have to lower my handelbar to compensate for a high-profile rim (COSMIC CARBON) in term of less drag?

(Why I ask is that I don't think that a high profile rim won't do that much in comparison to say bend your elbows or ride in the hood more often.)

I have read that 30% of the drag is from the bike...how much less drag will a high profile rim do???


Anyone?
//ArcSpin

pokey
07-23-02, 03:27 PM
It depends on your frontal area. Are you anorexic or tubbyesque? Riding in the drops works better.If your bud is fitter and peddles better,you are dead meat no matter what.
ArcSpin
07-23-02, 09:54 PM
Personaly I'm more towards the skinny type and I outride my buddy anyday but that's not the issue here.

jmlee
07-24-02, 02:59 AM
30% drag from the bike sounds a little high to me. The biggest factor in all aerodynamic questions for a bicycle is the total frontal area. This is hard to calculate to any high degree of precision. But, its pretty obvious that by lowering your head and body by 5-10 cm you cull a significant patch of frontal area from the total. How much frontal area is reduced by the aero rims? Good question.

I fully agree with you that even small changes in your position on the bike will do more than equipment changes. The speed you're going also matters. Below about 15-20 kmh, air resistance is too small to worry about. But, it goes up radically from there. So, get into a tuck on those descents.

What we often forget is that the pros who get all this fancy stuff for free have already optimized their riding positions, and are working to get an advantage of a few seconds over 200 km. Most of us are just not in the league where shelling out lots of money is going to help us that much. There is, of course, the "ooh, ahhh" approbation factor (a.k.a. the that guy's not very frugal factor), which is what the high-end bicycle industry is banking on. But, whatever turns ones crank.

Cheers,
Jamie