Current Projects chat and miscellany

The bigger issue with multiple rings on a hub gear is surely going to be that your drive ratio will be outside the manufacturer's recommended range, which means you'll be applying too much torque to the hub, which means either the hub's internal gears or the anti-rotation mechanism will break.

e.g.

And if it's a coaster brake version, you'll have a bad/illegal brake function (power, backpedaling angle).