Originally Posted by ferball
I was messing around today so I sandwiched a 50t and 44t sprocket together and it fit fine on the bike, my chain was not long enough for the 50t, but the concept looked like a solid idea. I think Jim's idea of only making it a 4t jump between sprockets is about right, 6t looked doable but I think 4t would work better. My current spring tensioner should do the job, just have to adjust for more play when I get my longer chain. Even if I can't get the derailer idea to work, I can stop my bike and kick the chain up or down a sprocket, then roll backwards about 3feet to set the chain on the new sprocket.
Any photos? I'll be interested to hear how it works out. It was a good idea you had! Yes, even if the derailleur doesn't work and you have to manually change the chain over to a different sprocket it would make a big difference in hilly areas. Did you add a spacer between the two? Weld it together or bolt it? Is it a rag joint connection to the rear wheel? What is the spring tensioner? Photos are good. I wonder how Jim is doing with the derailleur. He's a smart guy, so I imagine he'll figure something out. I want to thank you for sharing the idea in the first place.