Same crank length?
Yes, 150’s. Again, I think it’s that the smaller the wheel, the less force it takes to turn.
I have been mostly on fixed 29 for the past year, all muni, so I’m very comfortable riding a big wheel on technical single track. I built a 26guni last year, but didn’t find it practical for the trails I ride, so it’s been gathering dust. Last week I built a fixed 26 wheel; prior to the 29 I rode a 26 exclusively.
So far I have two rides on the fixed 26, the first ride was a little akward as I adjusted to the smaller wheel; I was also sick with a stomach bug. I noticed that climbing was easier right off the bat, the cranks (150) turned over easier and I had could maintain my climb over a longer distance. On this first 26er ride I cleaned a long (1/2 mile) climb that I had not been able to do without a UPD on a 29er.
On the second ride I was feeling better, the smaller wheel size was no longer akward feeling, again the climbing was easier. I cleaned another climb I had not been able to do on the 29er, this climb was short, steep, rooty and rocky. I was so excited about it that I started clapping, tried to give my dog a high five and he just looked at me 
One of the oddest things I found was that I started hopping, almost like it was instinctive. I am not a hopper outside of the occassional repositioning while holding onto a tree, but on the 26er I find that the smaller wheel is more conducive to hopping, so I automatically started hopping when I felt like I needed a pause before taking a line or when I needed to reposition on my line.
But, I still like the 29er for speed, flow, and the terrain smoothing effect. It’s nice to have choices 
No, the lighter the wheel, the less force it takes to turn. A larger, lighter wheel takes less force to turn than a smaller, heavier wheel.
It would seem logical to assume that if the difference in wheel weight is negligible, as it is in my case, the smaller diameter wheel would be easier to turn. If we take it to extremes, I don’t think it would be easier to climb a 30% grade on a 60" wheel vs a 24", even if the 60" wheel was lighter than the 24". You would never make it through the long arc of a single half rev!
If you clamp both unicycles in a bike stand and turn the pedals, if the wheel weight is similar and similarly distributed, they will be equally easy to turn. A 29ers’ weight is probably somewhat further away from the hub than a 26er, so there’s a small difference there, but it’s not the important difference. The important difference is the distance covered with each pedal revolution–the effective gear. Your effective gear is higher on a 29er by about 15%, which means that if you’re pedaling at the same cadence, you’re moving 15% faster on the 29er.
The one factor that is missing in your scenario is friction and gravity acting upon the tire and rider as he/she climbs a steep hill. And I understand about the extra distance per revolution, and tout that to people asking for my opinion on distance riding between a 29er and 36er. But the real test [for climbing] is which wheel size is easier, in general, to turn; for me and many others, including the testimonial from Nurse Ben, is that a 26er is easier to climb with than a 29er.
When I asked Kris if he thought it would be easier for me to climb with my marginally lighter 29er vs my G26er, he said he doubted it. Proof’s in the pudding as they say, and as usual, in all-matters uni, he was right. It could also be possible that if a person is more used to his 29er, then it could seem easier to climb with than a smaller wheel.
Another important question is not which wheel is easier to climb on, but which one was faster? Terry, it would be cool if you could go out and try the test again (maybe bring your 24 and 36 too if you have room in the car) and time the runs giving each wheel size your best shot.
When I’m climbing steep hills, I’m usually not trying to see how fast I can get to the top, but rather I’m focused on just making it to the top with even, deliberate pacing that won’t over tax my energy stores. Especially if there are many more steeps climbs to come!
When I did Fargo my only priority was to get to the top; if I had tried to go faster I would have most certainly failed. The beauty of the G26er is that in 1:1 it climbs like a mountain goat, and in high it’s a Cheetah!
One more thing to consider, in terms of practical riding: On rough ground there’s a limited part of the rotation where we have the most power to maneuver or crank over bumps. On a smaller wheel, this “sweet spot” comes around more often. Depending on the terrain, this may be a major factor for efficient climbing.
Kris
Excellent point! 
OK, come ride Mount Diablo with us. I’ll ride a 29er and you ride a 26", and we’ll see who’s more tired after 10 miles of climbing.
All else being equal, going slower is easier than going faster for short distances, so if you’re going slower on your 26, of course it’s going to be easier. Any extra effort on the 29er is going into extra distance and extra speed, which over non-trivial distances is likely to result in reduced overall effort.
Since the 26er’s smaller wheel allows you to spin faster than a 29er while climbing, the 26er will either keep up or beat the 29er to the top since the 29er requires more force per revolution. And as Kris correctly points out, the “sweet spot” comes around sooner on the 26er, so there’s less chance of stalling, especially over rough terrain.
Extra distance and speed is one BIG advantage of the G26er, which is far faster than a 29er in my experience. As we know, in high gear, the 26er adds and extra 50% speed and distance to each revolution, making it a virtual 39er. The other extra is that it has the added advantage of climbing easier than a larger wheel. Climbs like a mountain goat, runs like a cheetah!
That’s excatly what I had been hoping for, but in my experience it just wasn’t true on the goat end. For me, at least, when climbing the extra weight (and perhaps also due to slight loss of pedaling efficiency from the gearing, which nobody has mentioned) cancelled out the advantage of the smaller wheel vs ungeared 29. Cheetah, yes, but not uphill.
edit: To clarify, I’m not necessarily claiming the 29 climbs easier; I think overall the ungeared 29 and geared 26 climb differently, but with similar overall difficulty. Individual setups and body differences might explain some of the debate.
But the dead spot also comes around more often. 
Are you climbing steep hills in high? I always try to climb the semi-steep stuff in high, but most often I downshift for serious climbs so I won’t lose momentum. I would say that for the first few months I really noticed the hub weight, and felt that it definitely made climbing harder, but little by little I got used the the extra weight, and now I don’t really notice it.
I think in part that’s due to increased leg strength and more muscle mass created from pushing the gear in both high and also climbing in 1:1. So I still prefer my G26er for climbing to my 29er. And I don’t encounter “dead spots” as you mentioned, but definitely the sweet spots repeat more quickly, allowing me to sprint up hills pretty fast. But like crank length, everyone has their own individual preference.
Yeah, I’m comparing steeper hills in 1:1 vs 29 ungeared.
It’s entirely possible I didn’t give it long enough. Main reason I switched back to ungeared was because it was torture to ride with my son and stay in low gear the whole time, so it wasn’t worth having the money in a geared hub. It was also nice to get the cash to pay a small part of the medical bills resulting from riding in high gear on ice - which was about the most fun I’ve had on a uni, but only for a short time. 
Sorry about your accident on the ice! Did you consider keeping your GUni knowing that your son would improve enough to allow you to ride in high after a time? Or maybe your son could have ridden along with you on a bike, which would have allowed him to keep up with your GUni in high. And I’m not always going all out when I’m in high. Much of the time I’m just cruising at a nice sustainable speed in the 11-12mph range.
Wanna bet? How much?
Personally, I would never bet against Tom on a 29er
There are certain cadences that just feel right. They are going to be faster on a 29.