Flywheel

[kerf]

Seems like a solution in search of a problem. I've been riding bicycles for 50 years and starting has never been much of an issue, especially with an engine.

 

[Smerf]

In any event, the energy in a pedal driven flywheel would cost more effort than it gives.

Depends a lot on your riding style, getting it up to speed would take extra effort, but just like pedaling a heavy cruiser vs a nice light mtb once you get going you aren't really aware of the extra weight. This isn't just an oddball idea, it's actually being tested on race cars.


thinking last night, how about mounting it like a friction drive motor. Position it so it hangs back more, of course, so you don't lean into it. Then you could just use the wheel you were talking about and a cable system to drop it onto the tire for take off or spin up, and then raise it when it gets going. If you have it inline with the other two wheels you'll get the least amount of handling problems. It will probably seem a bit slower to turn in though.

 

[kerf]

I'm not trying to rain on the parade but the current direction in locomotion seems to be lighter rather than heaver. I increased the weight of my bike with the engine but it produces 16 times more power than I can. The road bikers are spending thousands of dollars on composite frames and wheels to get a 12 lbs bike. Wonder how many would like to add a 50-70 lbs flywheel.

 

[SirJakesus]

The beauty of a flywheel is that you could add lots of extra weight by using a heavy duty dual suspension frame, massive tires and rims and still have tons of push with little effort on take offs. The flywheel can be set up to relatively slowly regain its momentum when you're already at cruising speed so it wouldn't be too much of an extra load on the engine or pedals. When you want to take off again and that thing is spinning at possibly thousands of RPM theres a lot of stored kinetic energy there. If done right (or wrong) it could easily flip the bike. Nobodys saying this would be light or simple and in fact all of our bikes are neither. If it could be engineered and implemented in an elegant way you'd be more able to utilize the small amount of power these small engines can produce WITHOUT going beyond the legal HP limitations for a MAB. Not to mention it's a novel idea for a bike if it was worth the extra hassle and didn't turn out looking like a frankenmobile.

 

[nwguy]

I'm shooting for about a ten pound flywheel, so the weight won't be excessive. That much weight at the perimeter of a 26" or larger wheel spinning very fast has a ton of energy. I thought about a friction drive type engagement, but I'd rather have the flywheel be rock steady (not moveable), and engage it with an idler/tensioner. This is a pretty great video about automotive flywheel hybrids (flybrids):

http://www.youtube.com/watch?v=4PcIt0FPvWQ