What kind of flip/flop combos are you ENO singlespeed riders using? Do you have one cog for your uphills and then turn the wheel around to use a totally different sized cog for downhills? How much of a variance in cog size can the ENO hub tension? I hadn't put much thought into it and yesterday went out with a 17 fixed/16 free/36 chainring. I was fine going up the logging road, but going down I was really wishing I had a smaller free to bomb down the hill. Spin city. It got me wondering if the ENO hub could tension something like a 17/13 combo. Other than that is was a BLAST to have my Fat Chance back on knobbies!!

I've got 14 fixed, 15 free ENO Eccentric on my old Specialized M2 road. I haven't tried anything larger than 1 tooth. I've still got the 39 from the old Campy Chorus crank on it. I'll have to post a pick soon.

I'd like to know, too. I like a 3-tooth difference, and it'd be nice if the eno hub would handle that. I've got a nice old diamond back titanium mtb frame just itching for an eno wheel.

adding/subtracting a tooth adds/subtracts 1/8" (4mm) of chain. a 3 tooth difference would be a 1.5" change. the eno can adjust 15mm.

if you do the math, you can do it but then again, math sometimes doesnt equal real world. If you have chain stretch and such. I'd say you need to have very little slack with the hub in the forward most position with the larger cog and then have it in the furthest position with the smaller cog.

I really want to get the eno hub too. I converted my MTB to single (with a surly singleator) but want to go fixed now.

I would guess the ENO eccentric hub will handle at least 2-teeth, since the ENO Dos-speed freewheel comes in 16-18 or 17-19 combos.
Kinda spendy and whiteind.com doesn't have much technical info about it, but that might give you an idea of what the ENO eccentric hub has for adjustment.

I'm running one tooth difference (19 fixed/18 free), and I have relatively long horizontal dropouts, and I still wouldn't want to go more than 2 teeth, for fear of losing tension. There's also a limit to how far forward in a horizontal dropout I am willing seat a hub, so YMMV.

This is a bit off topic now, but man, I love my sub-11 dropouts. My bike'll take anything from a 14 to a 20 in back without changing chain length. I suppose that's a bit much to ask from an eccentric hub, though.

I wish my road bike was steel. Then I could put on dropouts. Debating over getting an eno and a new rim, eno and reusing a rim, or building a fixed roadie.