I am planning on building up a touring frame for single-speed/fixed gear and I seem to have two options, each with their own problems. Any input from you knowledgable folks in the mechanics forum would be welcome.
The decision is between 135mm and 130mm rear dropouts.
-If I use a frame with the touring standard 135mm rear dropout spacing, I could get a Phil Wood Kiss Off rear hub, which would be awesome. In order to get a straight chainline (the Kiss Off having a 52mm chainline) I think I would need to use the outer ring of an MTB triple crank. I haven't seen this done, but it seems like the chainwheel might be way too far out from the frame. Would this get in the way of my leg? Affect my riding? Thoughts?
-If, on the other hand, I use a frame with 130mm spacing, I could use a Phil Wood track hub. The problem here is that the 130mm would mean a weaker wheel, and thus one less useful for loaded applications. It would also mean less spacing for big wheels and fenders. Also, if I wanted to do a serious touring trip and add a deraileur, I'd be stuck with a smaller cluster. No?
If you're building a wheel for fixed-gear or singlespeed usage, strength of the wheel is not a worry that should push you to using a 135mm-spaced rear hub. Singlespeed/fixed rear wheels are usually dishless (spoke angle and tension are equal on both drive-side and non-drive-side) and these wheels are very strong. The extra 2.5mm on each side isn't going to do anything that you need here. And as you say, it would move your chainline further out, which is also unnecessary and only has downsides, such as an unnecessarily wide Q-factor, and greater likelihood of banging your calf on the chainring. If you can put a chainring on the inner ring slot, you can also mount a chainring guard where the outer chainring normally would sit.
You could also solve this problem from the frame's end - the Surly Cross Check (for example) has 132.5mm rear spacing, and of course horizontal dropouts (something that you should have, wherever you get it from). Lots of frames nowadays are going with 132.5mm spacing so you can use 130mm or 135mm-spaced rear hubs.
My Country Road Bob cyclocross fixed gear bike has 135 mm rear spacing. My bottom bracket spindle is 122 mm and I pedal easily with no rubbing on the chainring. I don't notice any Q factor problems, but that may be just me. Either way is probably fine, but if I had my choice I'd go with 130 mm rear spacing becasue it seems there are more hubs and bottom brackets combinations that would fit.
And again, given the choice it's more worth having your chain and crank and pedals closer to the bike's centerline rather than further. Q factor problems aren't something you'd notice, and not really a problem; it's just preferable usually (unless your hips are really wide) to have pedals closer to bike's centerline.