Thread: Amidesign.
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Old 10-22-2008, 05:23 PM   #8 (permalink)
trebuchet03
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The Miata - '01 Mazda MX-5 Miata
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Quote:
Originally Posted by amidesign View Post
As you see the tail of the most efficient vehicle of the world is a bit quite longer :

ETH - PAC-Car II - PAC-Car II Miscellaneous
The PAC2 is a very beautifully constructed vehicle... But, it's design goals (even the goals for the diablo2) are different than the design goals for a car replacement type velo.

A very supine position, very long body doesn't lend itself to be practical for daily use.

My long bike is occasionally too long to lock up everywhere - it's not a big problem at it's current length, but if it were any longer, it would be almost completely impractical for daily use.
Homemade Sport Utility Bike (SUB)

This vehicle, for example, is a very gentle taper... But it came at a very hefty compromise.... The pilot is laid back traveling head first and pointing backwards (the pilot navigates by looking through a mirror) - allowing your widest body part (hopefully your shoulders) to lead the vehicle. Aerodynamically efficient (for speed) - not practical for someone like me that would use the vehicle to commute, get groceries, etc :/



And remember, cD changes drag linearly... As does frontal area Blimps tend to have incredibly low cD values - but have a huge frontal area. If you start at a respectable .20 cD with a cross sectional area of 5000cm^2 - you'll probably find it much easier to reduce 50000 than it is to reduce .2 (reducing both would be even better - but it's important not to forget one for the other).

In short, I'm saying that on the velo scale, what's efficient for aerodynamics is not necessarily efficient for daily use. And that's where compromise fits in...
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