Originally Posted by
2old
The Trek (and all OEM mid-drives AFAIK) has a geared motor (look at the ebikesca tutorials for an explanation), and they're noisier than direct drive (DD) motors (mostly confined to the DIY crowd, Stromer and other hub-drive systems). IMO, the quietest motor will be a DD with a sine wave controller. A Brose mid-drive could be the quietest of the bunch since it has steel gears and can use a belt drive instead of chain for reduction.
If I was to use a DD rear hub motor ( 26" wheel ) with a sine wave controller would I still be able to run the same rear cassette ( 9-speed ) that I currently use? What would be the best brand to look into? Currently I am favoring a Bafang BBS02 mid-drive kit ( 750 watt ) since I found what looks like a reliable USA distributor that deals primarily with e-bike kits. I like the idea of dealing with a USA distributor direct because one; they can answer all my questions before I buy and if something goes wrong I can send the unit back more easily. Your thoughts....