For e-bikes, that is. After converting my first Trek to a rear hub e-bike, I have not once used my front derailleur. The chain remains on the highest chainring, and any gear changes happen on the rear 7-speed cluster. All my riding is on roads, not single-track trails, though our part of Pennsylvania is fairly hilly, so some shifting is required – not really single-speed territory.
I’m also finding that I can run a larger single chainring than I would normally use on a non-electric bike. My second build, also a Trek, is running a 48-tooth narrow-wide chainring, and my first build will soon be running a 50-tooth chainring. I’ll provide a few pictures below when the swap is complete.
Bottom line: There really doesn’t seem to be any need to use a front derailleur on any e-bike, rear hub or mid-drive. It’s just adds unnecessary cost and complexity.
Parts:
BUCKLOS 104 BCD Mountain Bike Single Speed Crankset, 170mm MTB Square Taper Crankset ($30)
YBEKI 50T Chainring 104BCD Round Oval Narrow Wide Single Bike Chainring ($24)
And the evidence:
And a ‘before‘ picture so we know where we came from:
PS – I rode 12 miles this afternoon and really like the change. With this new gear ratio (50×12 in the highest gear) I can still pedal at 35mph. 20mph cruise in the middle gears is perfect. Build #2 is running a 48-tooth chainring which is probably more appropriate for group and trail rides. Having a few bikes, each with its own unique characteristics, I find myself selecting the bike that best fits a planned ride.