[SarahB]

Originally Posted by JVN

The torque applied depends greatly on your motor combining, and what speed they are matched at. Especially if this combiner gearbox is designed to go straight to the wheel after (as Rob mentioned). The final sprocket reduction is limited by several factors. (Such as Chain size... note: I believe "national champion team 469" blew 1/4" chain like nobodies business towards the end)

Yes it does, however that torque is the same if you use a dog shifter or a shifter such as this. Plus he said he was possibly using 16 pitch gears, and steel 16 pitch gears are a lot stronger than your average shifter.

Keep in mind, his design doesn't even use #25 chain. While the reductions possible using sprockets is somewhat limited, its still pretty wide. Using #35 chain, you can get as much as a 3:20 reduction, which is pretty good. If you needed any more than that you could just change the ratios inside the shifter or add another box with another reduction after.