This might be more appropriate for the 'road' forum, but it's an old bike under discussion and I trust the collective judgement of C&V more anyway.
Planning the build for the atala I posted a few days ago, I've been having a lot of trouble settling on the drivetrain.
I've got a 28-38 double on my current bike, along with a 28-13 seven-speed freewheel. I've noticed that the only time I ever use the small chainring is when I'm pulling the toddler trailer up a steep hill, and then I only ever use the lowest possible gear. After cresting the hill it's back into the big ring. I don't feel too limited by the top ratio on the bike, as I can spin about 30MPH on the downhills and I'm not ashamed to coast.
I want a very low granny gear for the baby-pulling. While I feel like it "should" have some really tall gears just because it's a road bike, I'm pretty confident I'd almost never use a 50 or 53 chainring. ( Note that 120RPM burst with 50/11 is right about 43MPH
)
A triple crank seems so awkward, particularly since a tight cluster would put my cruising gears right on the low/middle chainring split. A wide cluster would mean I would almost never use anything but the middle ring. Similar problems crop up when considering a compact double.
I'm beginning to think that the best gearing for me on this thing would be something like a 40T single ring and a 9 or 10 speed MTB cluster like a 34 or 36 - 11. I'd have the low gears I want, a couple higher ratios than my current bike has, and I wouldn't have to mess around with a front derailer (thanks Sheldon) or left shifter at all. The biggest drawback of this plan is that it seems like it'd make the bike look stupid or somehow feel "wrong".
So, tell me this, C&V... what do you think about 1 x N transmissions?