Hey Cokeurs!
My cadence sucks when I use the bigger cranks (except when MUni).
As a long time Cokeur of 5 years, I’ve had 170mm, 155mm, 120mm, and even 89mm! 
I am considering 140mm from unicyclecom for distance riding.
My Coker brothers(and sisters?),
I’m asking all you veterans 36" riders, what crank size do you ride in and why.
Thanks. 
I don’t know if I could say I’m a veteran Cokerer, but I’ll take a stab at this anyway. I’ve been riding my 36er for 2 years or so, and I have had 150, 140, and 125’s on it. I like the leverage from the 150’s and the smoother spinning of the 125’s. The 140’s seem to give me the best of both. I can freemount reliably, and I can climb hills without too much effort. My cruising speed is also steady at 11-12 mph, which hasn’t changed from the 125’s.
Since square taper cranks are fairly cheap it should be easy enough to test the waters. I found my first set of 140’s on an old kids 10spd bike. I sawed off the chainwheels and I was ready to go. I bought my current set so that I could mount a disc to the spider for a disc brake setup.
Actually, let me know if you want my old steel 140’s. I’ll send them to you for the cost of shipping.
I started out with 150/125 moments. I learned with the 150 setting and then moved to the 125. 150 is way too choppy at speed. I now have 125/110 moments, and the pedals have been in the 110 hole mostly. I like the speed and I can still climb some pretty steep hills. For muni, I would probably want to go back to 150. Riding with 110s on the 36 has trained me to run my 24 guni with 125s for muni.
Depends what riding you want to do. 125s are easy enough on the flat and smooth. 150s are versatile. 170s are a bit plodding.
On the whole, it is better to learn to spin longer cranks than to use shorter cranks in the pusruit of speed. That way, you get the best of both worlds.
I have ridden with 150, 125, and 110 cranks on my Coker. I have settled on 125 mm because I can spin them at a reasonable rate (10-12.5 MPH averages) and I can still get up moderate hills without standing up. The 110s are fine for flat riding but I have to stand up out of the seat for more hills than with longer cranks. If I were riding up a steep road I might switch to 150 mm, but I have not done it recently. There is a quite steep bike route around here I might try with 150s. I have ridden the less steep section with 125s and it was OK, but any steeper and I will be out of the saddle the whole time, which is much less efficient.
Scott
152
I started with Coker 125’s. Did OK, but had trouble with freemounting, particularly on dirt. Switched to 152’s (Torker LX 6"), and really like them. I ride quite a bit on double track and even xc single track, so the added control is important for me. My commute on snow and ice today would also probably have been less fun with shorter cranks.
I’ve only been on the Coker for less than a year, and I’m certainly no speed demon. But the versatility from longer cranks has me hooked, and I don’t anticipate switching any time soon. 152’s for me.
Another note about the Coker cranks: they have a lot of Q factor, maybe even slightly more than the Moments.
140mm cranks have been my favorite. 125mm seemed too short for me.
110 for me seams the natural length. For going fast I put on 102 or 98.
I’ve tried 152, 140 and 127. I stick with the 150s because of their versitility, especially because I do city commuting (and hilly ones at that).
I feel safer with the extra control on the bumpy road surfaces and long lines of traffic. Speed is not a really priority even though it’s frustrating watching the average cyclist overtake me as I ride :(.
Also, free-mounting with 154 is so much easier. I’ve had too many frustrating incidents on the road with shorter cranks where it’s taken me ten minutes or so to get onto the uni.
It’s nice to hear of someone besides me that has been in traffic miserably trying to freemount on short cranks without success. I have 125/150’s. Like others, I like the 150 for control/hills, while the 125 is great for distance spinning on smooth, flattish pavement.
As you can see it’s a fairly personal choice. Not only does it involve your personal preference, it also involves the steepness of your rides, as well as what you’re comfortable with. New sizes take time to get used to, so don’t judge them in a couple of rides. Give them time.
In all my Ride The Lobster training, I couldn’t imagine riding with anything over 125s (and I didn’t). Since changing cranks is a pain, I don’t think I did that more than once or twice either. I mostly rode with 114s, and Nova Scotia is anything but flat. In fact, I think that’s the size that’s on my old Coker now (but I’ve neglected it since I got my Schlumpf).
I recommend starting with 125s and seeing what you think after half a dozen rides.
Mounting with short cranks? Don’t blame the cranks; that’s operator error. A little extra focusing on your mount technique will make it relatively easy to get started with all but the stubbiest of cranks, at least if you aren’t fully loaded or otherwise encumbered by huge handlebars and stuff…
I brought 125s and 110s to Vietnam for the 2008 tour, intending to use the 110s for the flat days and the 125s for the hilly days.
I put the 110s on for the first day’s ride… never ended up taking them off. Even Hai Van pass was no problem with the shorter cranks.
If the hills get much steeper than 8 or 9% I’d definitely go with 125s… but nothing longer on pavement.
Alas! though I prefer 125 for riding my Coker I still have bouts of freemounting fails… I suddenly can’t freemount the beast anymore 
the 140 is the most versatile for me and my preferred length but I may be a masochist since I stick to 125 