FWIW, Shimano offers only a twist grip shifter for their Nexus 3-speed. SRAM offers only a twist grip shifter for their iMotion 3-speed. Sturmey offers a twist shifter, two kinds of thumb shifters, two kinds of trigger shifters, a bar-end shifter, a downtube shifter and a dual paddle shifter.

Neither Shimano nor SRAM offer any IGH internal parts support in N.A. You can get any part you want for a Sturmey.

That doesn't bother me, I'd prefer grip shift, actually.

The parts support does concern me a bit, though. Not too much, if it's a good enough design to not NEED parts support, but it is a concern.

Leaning towards Sturmey due to dropout spacing, though, and I like the X-RF8(W) on my trike. So, any downside to the current S-RC3 over the current AWC?

I used Sheldon's calculator and did some calculations on the Dahon Boardwalk. (Shimano Nexus 3, 170 cranks, 44T chain ring, 15T cog, 20 X 1.75 tire)

Result:

1st Gear ----- 44.2 inches
2nd Gear -----54.8 inches
3rd Gear------74.7 inches

I like this setup because a 55 inch (I prefer 54 inches) gear will allow me ride all day. You will spin out easier but you'll learn to control your speed and trust me, after 30-40 miles of riding you'll wish for a lower second gear. I still think 44.2 inch 1st gear is too high when the hills come, it would be even higher if you chose to ride a high second gear. I consider 3rd gear waaaay to high for casual riding and only good when going down hill.

Have you decided what second gear you prefer to ride all day with?

I was thinking 48/22 (stock 48T chain ring).

That would give, with the Nexus Inter-3, 29.9, 40.8, and 55.6 GI - pretty close to the 56.0 GI in top gear that the stock 48/16 gearing gives. This is a pootle bike, and I'm slow. 2nd and 3rd gear in that setup would be my normal use gears, 1st would be the climbing gear, and it just wouldn't have a downhill gear. The Automatix or the Duomatic would be in the same ballpark, just missing the first gear.

FWIW 48/22 is exactly what my Nexus 3-speeds are. Third gear is almost almost always fine once up and running, even on most inclines. I'm sure the pedals spin out about 20 mph. Second is low (starting off, pavement speed). Third is emergency low-gear, it was handy in the snow.

At first I did think about raising the gearing but now I'm glad I didn't.

Of all the reasons not to take a trip on the bike, I've never found 'not fast enough' to be one of them.

In a reasonably flat city, I was very happy with the 37, 50 and 68 g.i. ratios on my folder.

The SRC3 will have a beautiful, polished alloy hub shell with thicker flanges and nicely radiused spoke holes that won't need spoke washers. If you're after more of an 'old school' look, go with the AWC.

Ended up going with a used Sachs Duomatic - I really like the simplicity, and the fact that I won't have to have the frame widened - and I'll run 48/22. Hub is at the LBS, and they'll call me when the wheel is ready.

That'll give 40.8 and 55.5 gear inches. Good enough for what I actually use this bike for, and it is quite a bit faster off the line (although not up hills) with 56.0 GI, than my trike was with 34.4 GI (although once the trike is rolling, it can get rolling pretty fast, because it has better aero than the bike) - then again, it's probably not much more than half the weight of the trike, so there you go. (Trike's far better with the 26.9 GI first gear it has now, though, and due to the shallower chain angle around the first idler (did it with a smaller chainring), I seem to lose less power, too.)

Trike? 3 wheels?

Yeah, this is what I normally ride (the folder being for when I want to go less than a mile or so, or when I want to cycle when I go on a trip (much easier to travel with the folder than with the trike)):

http://bhtooefr.org/images/terratrike4.jpg

Recumbent tadpole, has an 8-speed Sturmey-Archer wide ratio hub on the rear wheel, and the front wheels are steered. Just switched from 46/25 to 36/25 (and the hub is a gear-up hub, so first gear is direct drive).

Nice... does it come with a vibromassage option? ;) I haven't ridden a Terra but have done a few miles on other trikes. They're just so comfortable yet surreal... they're like sitting on a La-z-boy (so you expect a TV in front of your face) but much faster and you're getting exercise.

Damn thing is already too heavy as it is! 40 pounds before adding fenders, rack, mirror, accessory mount on the end of the boom, seat bag, flag, tail light mount, and then lights, GPS, tools+spare tube (which probably pushes it over 50 pounds), plus panniers, whatever I'm carrying, and me!

But other than it being overweight (nothing gearing can't solve - it WILL get up a hill, it just might be a bit slow), and it not folding (seriously, if I do this again, it'll be an ICE Sprint, I think), it's quite nice.

Ditch the flag and you'll be faster... weight and aerodynamic advantage. LOL

The cool thing about trikes (and 'bents) is that the backrest provides a stop to push against while pedaling so you can 'muscle' up the hills and develop tree trunk sized legs.