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Old 01-07-2013, 11:59 AM   #40 (permalink)
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Originally Posted by NeilBlanchard View Post
The Elio Trikke(?) is front wheel drive - you can see the drive shafts in the video and/or the photos.

When the second person is onboard is when it will be the most "Cg challenged". The double lane accident avoidance maneuver test (which is taken at 45+mph) is what did in the Aptera;even though the front wheels on that were almost 7' apart, and the battery mass was low and forward as possible. The early prototypes were probably fine, but as they went to the "production ready" S0-1 they gained a whole lot of weight, and when the front suspension rolled to the side, the rear wheel was lifted onto an outer corner.

The Messerschmidt some linked to earlier in this thread was very unstable. The Cg must be as close to the two front wheels as possible; and they may regret shortening the wheelbase. The longer concept would be lower aero drag and more stable, all else being equal.

...that's why there is such a thing called 'The Golden Rule of Trike Design'. The first recumbent tadpole bike I made had very peculiar center-of-gravity shift dynamics, especially in hard turns. It had a penchant of quickly tipping me over. The Cg was largely biased towards the front axle but apparently it wasn't enough. The trike's rear passenger/cargo load will compromise spirited driving. Unless it has a tilt-turning geometry but still...follow the rule or else.


Last edited by botsapper; 01-07-2013 at 07:09 PM..
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