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The bike does have a different position for the rider (recumbent). But aerodynamics are key so I wonder what Graeme Obree comes up with.
Looking at the video the powering mechanism seems to resemble a go-cart, rather than conventional bicycle. It is hard to see clearly, but it does not look completely like a circular action. I wonder whether the aero advantage he is capturing in this way is outweighed by the potential for a loss of power.
What I love is that rather than endlessly model in the lab, he just gets on with it and finds out.
So far, from the video, stability and potential over-exertion just getting beastie up to speed seem to be challenging factors. A smooth circular pedal strong might help that... but I am no engineer and he is the mad tinkerer. This will be great to watch develop. Like NASCAR, entertaining high speed but really just waiting for the bone crushing impact to occur.
However, I'm not so sure about this new bike. I see a couple of key design flaws:
- more driveline friction by using the stair stepper drive
- his frontal area is not small. It would be best to put the rider between the wheels so truly minimize the area
- breathing while laying on your chest has to be more difficult than when on your back. what's the power impact of that?
- seems very unstable. For a straighline top speed machine I'd use a very, very relaxed geometry so it practically goes straight by itself.
I really hope he proves me wrong and set the bar up a notch!
The front wheel seems perfectly ideal for a lefty type fork. The crank should simply be at the back to save so much additional leverage and energy loss and weight. That drive train is just nuts. Also needs a bit more trail to remain stable.
Waist needs to be tightly fastened to provide counteracting forces to the legs, otherwise, every pedal would move the body forward.
I imagine he is leaving at least 15-20% of efficiency out with that device.
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