Creativity Pool Forums

Over the past two days, I have been working through a new idea of mine. My idea is a complete design change for bike gear systems. Something that can enable gears to be shifted without the bike moving. If you know a thing or two about engineering, gears, or mechanics, I'd like to talk with you. I'm having a little trouble thinking of a way for part of my idea to work. Well, if you think you can possibly be of some help, email me (email removed). I'll explain my idea and problem further.

Being just out of high school, I doubt this idea will go anywhere too fast. Still, I'd like to see if its possible and if it works.

Im not an engineer but have had alot of experience with bikes.
Ill give it some more thought but all i can come up with now is
to have a way to shift gears while backpeddling. Otherwise somthing that is powered electrically with magnets might work.


let me know what you find

Perhaps you could consider a method of increasing and reducing the front or rear sprocket diameter to change the gear ratio. This idea does not lend itself particularly well to a chain drive, though hinges between the teeth are a possibility. Maybe it would be easier to accomplish with a belt drive or even driveshaft configuration.

I hope that helps. greghill

greghill wrote:Perhaps you could consider a method of increasing and reducing the front or rear sprocket diameter to change the gear ratio. This idea does not lend itself particularly well to a chain drive, though hinges between the teeth are a possibility. Maybe it would be easier to accomplish with a belt drive or even driveshaft configuration.

I hope that helps. greghill

That is exactly what I was thinking. Ironically, a few weeks after I thought of this idea, I read a popular science article that showed this exact concept. This is the website of the bike & article - http://www.ellsworthride.com/. I found out that changing gear diameters is properly called continuously variable transmissions. More on CVTs - http://auto.howstuffworks.com/cvt2.htm

Many years ago they produced a bicycle with hub gears which you no longer see. They were totally enclosed in the hub so preventing the ingress of mud or water. Gears could be changed without movement of the pedals. A design based on these principles would be welcome.

http://www.sheldonbrown.com/nexus.html