Advantages of deep section wheels?

[User16625]

How noticeable are the aerodynamic effects of a 5cm section rim over a standard one? Just how deep does the rims need to be to offer any real advantage to a 20mph rider all else being equal?

 

[Pale Rider]

I suspect the only advantage is for the manufacturer - more space for logos.

 

[Keith Oates]

I'm not sure what advantages there are but one disadvantage is that they 'catch' a lot of side wind at times!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[GrasB]

How noticeable are the aerodynamic effects of a 5cm section rim over a standard one? Just how deep does the rims need to be to offer any real advantage to a 20mph rider all else being equal?

Depends on how aero the rest of the bike is. Put aero rims on a loaded to the gills touring bike & it'll be almost unnoticeable, put them on a TT bike or a really sorted recumbent & you'll be able to feel the difference between the different shapes of deep rims over an hours ride. The actual quantitative difference? Using 28mm rims & a zipp 404/808 FC combination on my fast bike is about 8w I think.

I'm not sure what advantages there are but one disadvantage is that they 'catch' a lot of side wind at times!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Only if they're 'NACA' profile or flat sided. The more interesting shapes being produced by the likes of zipp & HED are catch far less side wind, due to their shape they'll tend to turn it into almost pure forward or rearward drag (rearward drag being the tailwind effect )

 

[Keith Oates]

I wasn't aware of that so it just shows "you live and learn". Thanks for that!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[MikeG]

I wasn't aware of that so it just shows "you live and learn". Thanks for that!!!!!!!!!!!!!!!!!!!!!!!!!!

I am sure GrasB is probably correct, although I have no way of knowing. However, be very careful of assuming you are learning anything from unsupported postings on the internet. A link to a published article on the subject would give you more confidence. This isn't meant as casting aspersions on GrasB at all..........I'm merely suggesting caution about the idea that "you live and learn" as the result of one anonymous post on a forum.

 

[Keith Oates]

You must be a joy to talk to in a pub !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[Herzog]

50mm rims are more than manageable in most wind conditions, anything deeper and it starts to get interesting when the wind picks up.

As to the aero advantage, useful, but not astonishing; rider position plays a far more significant role in aerodynamics.