Originally Posted by
spambait11
I’m liking IGH too and would put up with weight for a straight chain line (even when folded), but too wide of a rear triangle adds to the dimension of the fold. Also vertical dropouts may be out of the question depending on where your bike folds because of needed chain stretch.
Another disadvantage to IGH is that they’re pains in the butt to change tubes for rear flats.
Straight chainline isn't why I'd prefer an IGH. I don't want to worry about a chain developing a stiff link after a single wet commute, or deal with uneven cassette wear. Also, I like to have the ability to shift when stopped, or when freewheeling: I particularly like the freedom to shift up a ratio or two when freewheeling to blind curves or yields. I don't have to think about keeping the chain moving, and can concentrate entirely on the next driver out there that's trying to kill me. Also, I can dump both gears fractionally quicker as well (though
nothing beats a 4-speed Sturmey-Archer trigger from the 1950's though).
Vertical dropouts are irrelevant to a folding mechanism. The axle remains in the same location (relative to the dropouts) when the bike folds, regardless where it folds, or what type of dropouts it has (or track ends, or a through axle). If the design requires the chain to extend or contract in length on a non-derailer bike, then the design requires a chain tensioner, not horizontal drops. The dropout design remains entirely irrelevant.
As for IGHs being a PITA for flats: That's a function of failed engineering, not the IGH itself. Sturmey-Archer had quick-release indicator chains in the 1930's. Shimano makes the SM-CB90 cable Q/R, which would be nice if it had a provision to clip to a chainstay or was small enough not to interfere with cable routing. That said, there's no reason an IGH-specific cable Q/R can't be developed.
For that matter, complicated IGH cables are a recent phenomenon. Used to be that you could unscrewing an old AW (or Shimano 333) indicator (or bellcrank) and put it back on easily. Now we have the rotary design which is nice and smart, but a PITA to service. For the few legacy hubs with classic indicator chains, Sturmey now putts a crap ton of chingaderas in the way which make pulling the wheel more difficult than it has to be.
I will say one thing though: Rear-facing ends and chaincases combined with poorly-fitting fenders that don't allow a tire to clear...now that's a pain I don't want to discuss.
-Kurt