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Old 09-25-2011, 06:55 AM   #53 (permalink)
Frank Lee
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Blue - '93 Ford Tempo
Last 3: 27.29 mpg (US)

F150 - '94 Ford F150 XLT 4x4
90 day: 18.5 mpg (US)

Sport Coupe - '92 Ford Tempo GL
Last 3: 69.62 mpg (US)

ShWing! - '82 honda gold wing Interstate
90 day: 33.65 mpg (US)

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For FFs these problems chiefly amount to sensitivity to turbulence, where the vehicle is noticeably buffeted by turbulence, typically on motorways, at speed, in traffic. Ideally an FF should be “Indifferent” to these disturbances.
I'm still stuck with the idea that they had a CP ahead of CG, or a high CP, or CG in a bad place regardless of CP i.e. in relation to the tire contact patches, or something because I'm not convinced that a sleek shape is by necessity more sensitive to x-winds/turbulence and it must be intentionally sabatoged to increase stability.

Poor indifference is caused when attached (laminar) airflow over a surface changes direction or pressure. Sideways lift generated across a smooth nose may be balanced by sufficient tail area but the sudden cessation, or reversal of the airflow will instantly cancel the side load and this will be felt in the steering or attitude of the vehicle.
This is just a kinda strange way to say that even if a design has proper tail area to weathervane into a side wind the way we like it to, if the wind suddenly stops or reverses the driver will not be oblivious to it; he'll feel it in the steering and/or the way the bike tilts.

In that last bit he's talking about how much boattailing the bodywork should have when viewed from above i.e. "plan view". And he's saying there shouldn't be any boattailing in that dimension or else it will separate, which I am not believing.

Craig reports good handling dynamics; there's another guy on here that's ridden Craig's scooter too and IIRC he said it was good. Allert reports good stability with his design too. So the bottom line is, if you believe these guys (I do) then you can have a full bodied bike with good manners. BTW Craig's bodywork is very much boattailed in plan view so where does that leave the Voyager guy?

Last edited by Frank Lee; 09-25-2011 at 07:01 AM..
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