Panoramic
07-11-04, 06:00 PM
If you're familiar with what I"m talking about, I'm wondering why wheels can be around 2 inches in length (not circumference, but distance towards the hub). Any ideas?
Thanks
Thanks
Road Cycling - Those elongated rims you see on the TdF
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BlueDevil
07-11-04, 06:14 PM
Are you talking about the aero rims??
(http://www.cobr.co.uk/acatalog/tilium_carbon_200.jpg)
They are more aerodynamic than a normal wheelset. I have heard that the wheels cause anywhere from 50-70% of the drag on a moving bike at a high speed. Thus, when you are moving over 20mph or so, a set of aero rims can really help you. However, they do have their disadvantages.. in a cross wind they can get kind of hairy. Also, since there is more material, they will be havier than a similar non-aero rim of the same material. Finally, most of them are made out of carbon fiber, which has very bad breaking when in wet conditions.
(http://www.cobr.co.uk/acatalog/tilium_carbon_200.jpg)
They are more aerodynamic than a normal wheelset. I have heard that the wheels cause anywhere from 50-70% of the drag on a moving bike at a high speed. Thus, when you are moving over 20mph or so, a set of aero rims can really help you. However, they do have their disadvantages.. in a cross wind they can get kind of hairy. Also, since there is more material, they will be havier than a similar non-aero rim of the same material. Finally, most of them are made out of carbon fiber, which has very bad breaking when in wet conditions.
Panoramic
07-11-04, 06:31 PM
Thanks. I had a theory that it was pointless b/c it's harderr to turn given the gyroscopic effects of more mass, and maybe harder to turn the wheel into the wind
BlueDevil
07-11-04, 06:38 PM
Thanks. I had a theory that it was pointless b/c it's harderr to turn given the gyroscopic effects of more mass, and maybe harder to turn the wheel into the wind
The rims the pro's ride on are probably lighter than any rim you or I, or any mere mortals with mere mortal checkbooks ride on ;) . Those wheelsets are probably $1500-$2000+ (eek!). I have a set of semi-aero rims (Shimano 7701's). They aren't nearly as deep dish as the true aero rims, but are just over what is considered to have an effect. You can definitely feel the difference over 18-20mph..
The rims the pro's ride on are probably lighter than any rim you or I, or any mere mortals with mere mortal checkbooks ride on ;) . Those wheelsets are probably $1500-$2000+ (eek!). I have a set of semi-aero rims (Shimano 7701's). They aren't nearly as deep dish as the true aero rims, but are just over what is considered to have an effect. You can definitely feel the difference over 18-20mph..