Originally Posted by
fietsbob
There are a few overdriven internal gear cranks to multiply the smaller gear to act like its bigger though physically not..
1: 1.6..
My bike is 2013 and the bb is too thin at 3mm's for a speed drive crank. Utah Trikes told me that 5mm's is standard for the speed drive. Also Max Yeh from Pacific Cycles told me the same. But Max told me that the chain and sprocket are #25 size so I'm going to try changing the sprocket as the chain tension has room for adjustment.