I read a little more elsewhere and apparently the very small rear cogs do have a few watts more drivetrain friction - which is enough to sway races, and maybe hard road riding, but it seems well below 5% for a class 3 hub motor e-bike like ours. Given that we are already limited to a 1x drivetrain, the net loss may be negligible, given the smaller steps between gears enabled by a smaller chainrings. Like gravel, we are not riding in optimal conditions (uninterrupted perfect roads, no traffic, peloton, etc)Thanks for that link -- very informative and nicely written. Gravel gearing seems like a good starting point for a 60-pound ebike that you might have to ride home on a dead battery -- especially if you live in a hilly place, run hybrid to fat/knobby tires, and prefer lower PAS levels when you still have juice.
Just one small niggle: Judging from some of the jaw-dropping ocean-view mansions and $500,000+ cars I see around San Diego -- especially in La Jolla and Del Mar -- I think some of these folks could afford to have roads repaved before their rides.
Also the 38t is the lowest you can go without changing the crankset on a juiced, and I'm not sure there's much net benefit to going lower anyway.
Lennard Zinn put 1x and 2x drivetrains to the test at CeramicSpeed USA's laboratory to discover which produces more friction.