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Old 12-23-2012, 08:30 AM   #8 (permalink)
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Let me add another important possibility - and that is tunable suspension. It is likely (though possibly not) true that low rolling resistance means a stiff tire, with the only large scale flexing being for the purpose of keeping a good contact patch on the road - but the tire ideally would probably not act like conventional pneumatic ones.

So, already the requirements on the suspension are different: a pneumatic tire absorbs about half of all the bumps - all the small ones - while an über-low rolling resistance tire *probably* would not. The suspension would then have to be much more compliant in the first small part of the motion, and then it would have to be progressively less compliant and higher compression dampening and spring rates.

So, these together would be roughly the same with heavier loads - the über-low rolling resistance tire already would be similar to a higher pressure pneumatic tire. And since the suspension would be the area that would be most affected by heavier loads with either kind of tire, I don't think this is something we need to particularly worry about.

The suspension *does* need to be considered for both ride height and level attitude, when the vehicle is a low aerodynamic drag. If a heavy load is put in the vehicle, the ride height and/or the normal angle of the body will be affected - so the suspension on a low aerodynamic drag vehicle would ideally be able to level itself and compensate for load changes. And this would have the ability to work correctly with very low rolling resistance tires, along with a low aero drag bodies.
Sincerely, Neil
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