Help: Mechanical Odometer Answered
I have a bicycle trailer that I use for groceries and such, and hope to use for extended bicycle trips. I would like to get or construct an odometer for the back of the trailer, to advertise how far I've traveled. I've looked around a lot, but have had difficulty finding an non-electric or large-display DIY odometers (ideally, I would like the numbers to be 2 to 3 inches tall, and would like to keep it below ten pounds).
I would prefer it to be mechanical only, requiring no batteries or electrical power, but am willing to give on that point for the sake of simplicity of design, weight and cost.
If you have any advice where I could find advice or instructions on how I might set something up, I'd greatly appreciate it.