I'm working on a new counter design, one that uses spur gears rather than a chain. The counter will be legible from a seated position and uses commonly-available parts.
The main drive gears are replaceable in the event of wear or failure, although in their intended application they transmit up to 3 hp. I don't anticipate many failures due to stress.
It will require a bit more setup in fitting to the bike than the old JO counters, and therefore isn't as transportable from bike to bike, although the install is far from permanent.
Once I have a working prototype or CAD drawings, I'll let you know.
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