Not being blessed to have a degree in engineering, I am wondering if the movement of the pistons in the F6B in relation to the frame mounting contribute to the incredible smoothness? This combination has been around since the inception of the gold wing.
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The flat horizontally opposed 6 has self canceling vibration characteristics because there is a piston at Top Dead Center (TDC) on each side of the block at the same time. One piston is on the compression stroke and the other piston is on the exhaust stroke. This design provides the notorious smoothness of the F6B motor. Some automobiles like the Subaru's display the same smoothness as they have a flat motor design and opposite pistons at TDC simultaneously.Originally Posted by Retired Army
From Wikipedia
The movement of the pistons in a horizontal engine is all in the same plane, so it creates less vibration than in a V-configuration engine; particularly one, like a V6, with an odd number of cylinders on each side of the engine. Unlike the V6 but like the inline-6, the flat-6 is a fully balanced configuration which is in perfect primary and secondary balance. The three cylinders on each side of the crankcase tend to have an end-to-end rocking motion, like a pair of inline-triple engines, but in the usual boxer engine configuration, the imbalances on each side cancel each other, resulting in a perfectly smooth engine.
The flat-6 is also smoother than the flat-4 or inline-4 because the power strokes of the cylinders overlap in a four-stroke cycle engine. In these four-cylinder configurations, pistons are 180 degrees apart in crankshaft rotation and start their power strokes every 180 degrees, so each piston must come to a complete stop before the next one commences its power stroke. In the flat-6, each power stroke begins 120 degrees after the previous one starts, resulting in 60 degrees of overlap between power strokes and a much smoother delivery of power to the flywheel.
The engines relationship to the frame has virtually ~nothing~ to do with smoothness. The opposed cylinder design is what does it.
There is also an opposed cylinder opposed piston design out there than looks interesting;
http://www.ecomotors.com/
Turbo 2 stroke. Power to weight/power to size ratio (power density) and efficiency are both very impressive.
The technology of Opposed pistons isn't 'new',,, the diesel engines in some of Germanys WW2-era balloons had a similar design in the Junkers Jumo 205 aircraft engine:
http://upload.wikimedia.org/wikipedi...cutview_02.jpg
The OPOC looks like it's getting support from / going to be built in China:
http://www.motorauthority.com/news/1...built-in-china
http://www.greencarreports.com/news/...piston-engines
The piston-equipped engine, as we know it, is long overdue for a refresh,,,
BMW's boxer seems to have started something.
Volkswagen's opposed four and the original Wing design differed mostly in cooling.
In the Forties the first helicopter engines were air-cooled opposed sixes specifically to reduce vibration in the airframe.
Honda didn't do anything new . . . they just did it BETTER!
Thank all of you for the great information.
Riding a Goldwing is like opening a can of testosterone.
Go Green - Recycle Congress!!!!
now lets work on world peace!
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