suspension yea or nay

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AuotonomousRX
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Re: suspension yea or nay

Post by AuotonomousRX » Sat Apr 19, 2014 9:01 am

I do wonder about the Inherent Stability of a 2 Wheel FF Design at these high speeds, because of the very low CG and the Load Distribution.
Honda experimented with Lowering the CG in 550 GP Bikes and found it markedly upset the Balance of the Bike and made the Bike unstable.

I can't see why the target can't be achieved under the Existing SATA APS Rules, if it's about low Frontal Area reducing the Aero Push.
A number of Bikes noticeably Tom Mellor's Triumph, Bones' current Bikes and Tom Borcherdt's (aka Koncretekid) BSA would have a Frontal Area with the Rider in Position approaching the FF Design?

Image

I also like the KISS Principle.

Pete :D
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Pete :shock:
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ChrisACT
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Re: suspension yea or nay

Post by ChrisACT » Sat Apr 19, 2014 10:00 am

Honda's under-slung fuel tank didn't work because centre of gravity isn't the primary issue with motorcycle handling in the way it is with cars.

Mass centralisation is probably the big deal with bikes. Hanging the tank under the engine distributed the mass instead of centralising it.

With a FF bike, who knows?

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AuotonomousRX
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Re: suspension yea or nay

Post by AuotonomousRX » Sat Apr 19, 2014 6:57 pm

ChrisACT wrote:Honda's under-slung fuel tank didn't work because centre of gravity isn't the primary issue with motorcycle handling in the way it is with cars.

Mass centralisation is probably the big deal with bikes. Hanging the tank under the engine distributed the mass instead of centralising it.

With a FF bike, who knows?
That is what I am talking about Mass Centralisation. My understanding is that lowering the CG on a 2 wheeled vehicle creates a Pendulum effect, might be controllable at slow speeds, but at 300 mph on bumpy Salt???

Remember the discussion is about a sit in Bike, not like a Streamliner that has a Roll Cage etc.

I am raising it just in case this type of Design might be inherently Unstable at high speed.

Pete :D
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Pete :shock:
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rgn

Re: suspension yea or nay

Post by rgn » Sat Apr 19, 2014 7:00 pm

The 1984 Honda NS500 of Freddie Spencer had the experimental underslung tank, it handled well enough to achieve forth in the championship out of a field of 27 riders, but it did have some problems changing direction, and with understeer. Next year honda turned the bike the right way around and Freddie won both the 250 and 500 titles in 1985. Here's a fun vid of the bike and Freddie in action.

http://www.youtube.com/watch?v=oU_RQy26CGk

David Leikvold
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Re: suspension yea or nay

Post by David Leikvold » Sat Apr 19, 2014 7:45 pm

Greg,

The only thing I like about that bike is the front fairing. It is front wheel drive and rear wheel steer. I am yet to be convinced that that is going to be an advantage :shock:

Cheers
Dave :mrgreen:
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AuotonomousRX
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Re: suspension yea or nay

Post by AuotonomousRX » Sat Apr 19, 2014 9:11 pm

Ralph

I believe the "Radical" 1984 Honda was the first NSR500 V4 and was so bad, Freddie got Honda to bring back the 1983 NS500 Triple mid season.....the NSR did win 4 races but only on tracks with a "Honda Lane"....

... any way..... moving on.....

I would simply like to think any 300mph Bike would need to have Inherent Stability. We can change designs but not Physics, that's all I am saying.

Pete :D
Metric Target 250 on a 250 on a Red Bike

Pete :shock:
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