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Comment by maym86 | Hacker News Reader

Would it be possible to build a bike like this but with multiple gears to get to speed from a standing start and not be towed? Is 100mph tow detatchmemt a required limit for the record?

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I think you could, but you'd need a long way to get up to speed. The power needed to accelerate (Force=Mass*Acceleration) would be huge. I would imagine it would be a lot greater than steady state, where the only thing slowing you down is wind resistance. The windblock was clearly designed to minimize that force.

I don't feel comfortable going much of 80mph sitting in my car.. I can't imagine doing it on two wheels. I don't think my car actually can go that fast...

Well the power needed to get from 100 mph to 183 is a lot more than from 0 to 100, at least in kinetic energy terms which is proportional to velocity squared.

I think the main problem is that you'd be tired out getting to 100 mph, but that with the gearing so high it would be very difficult to start from a standstill without tipping over.

I thought about that too. I'm not sure how big spacing you'd need between gears so the jumps aren't too abrupt. You probably want something like a motorcycle transmission to handle the high speeds. Maybe something like the pinion gearbox but with much higher gears and larger spacing to get you to 200mph at a reasonable cadence.

The front chain isn't moving any faster or enduring any more intense forces than a normal bicycle drivetrain, so it can be replaced by an off the shelf road bike gear set. With a 30-speed drivetrain this could provide a low gear that's about the same as the high gear on a road bike, so it would probably be possible to get moving from a standstill. In the highest gear, you'd be able to go at least 160mph pedaling at the same cadence that was used to set this record. And that's just with the off the shelf components. A custom set of gears could probably stretch out the ratios enough to provide a high gear that's equivalent to the record-setting configuration.

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