Me and ben don’t think a 27.5 will fit in a 2012 Kh 26 frame
Wes and I scoped it out on his KH 26 (mine now), and the Duro 3" clears with 1/2" to spare. The 650b HDSG is an inch + taller that the Duro 26 x3", so even if clears, it’s so tight that it ain’t gonna work for anything but dry.
However, a 26" HD SG will fit 
Wes seemed to think a Nimbus II 26" frame had a taller crown, so that might be an option.
Not sure about the Oracle 26", maybe someone could take a measurement…
Yes? 
I’ll help if I can, let me know what dimensions you’re looking for and I can compare them to my frame if you want.
I’ll check the frame height on my 26" Muni when it gets here. 
I’m hoping the new Dirt Wizard’ll fit in there, but I may also run the HD SG at some point as well. First I wanna see how I like the Duro.
As for tubeless, I ain’t gonna mess with it on this uni for now. If I felt like throwing a uni out the window I’d just go try to add some sealant to my 36er.
I had a friend measure a nimbus 26 frame and its 2.5in pf room to top
That’s for sure.
I thought the concern of NurseBen was about fitting the new Dirt Wizard in 26x2.75 under the KH26 crown.
For the 650B adventure, better stay on the safe side and use a 29er frame 
According to the rumors, the Dirt Wizard 26x2.75 is supposed to have about the same height as a 650b wheel. No mention of what 650b tire it is being compared to though I’d assume it’s something like a 27.5x2.0 rather than a larger tire like the 2.35 HD Ben is using. Another possiblility is that the Dirt Wizard has a diameter of about 27.5" so they can say it’s the size of a 650b wheel without any direct comparisons. I’m hoping for the former.
Update on the Knard 29 x 3 fit on an Oracle 29 frame:
I had a little knobby rubbing when I was standing to peddle, not enough to slow me down, but I could feel and hear it.
Sooo, I cut off the offending knobbies 
It really wasn’t that hard, I used a razor knife and simply nipped the knobbies that run along the outside edge of the shoulder, probably took an 1/8" all the way around on both sides.
The fit is now fine, no more rubbing, clearance is about 3/8" on both sides and 1/2-5/8" to the crown.
What I read was that the stated width of “2.75” was a joke, poking fun at the 27.5" wheel size 
Seems like it would have been easier to put a piece of sandpaper around your frame leg where they rubbed and then just ride it a mile or two. I guess that would leave you less room though.
From the Surly catalog: http://surlybikes.com/uploads/downloads/Surly_2014_catalog.pdf
Rumor suggests a Fall release…I’m good for one 26+ to replace my Oregon 4" tires
DIRT WIZARD 26+
An aggressive tread focused on traction and control
in loose and varied terrain, with beveled leading
edge dual row knobs in the center and well-spaced,
siped edge knobs to dig into loose corners. Designed
to be run on 50mm rims, the 2.75˝ casing inflates
about 27.5˝ overall diameter (that’s pert near
650b, folks), meaning you get some benefits
of a larger diameter tire like ground approach
angle and more footprint, with easier maneuverability
of a smaller diameter tire, plus some extra
pneumatic cushioning. Minimum rim size for these
bad boys is 35mm.
ETRTO: 622mm
Casing: 120tpi, folding bead (850g)
27tpi wire bead (1070g)
DIRT WIZARD 29+
A 29˝ version of the aggressive, trail gobbling,
traction- and control-focused Dirt Wizard tread.
Dirt Wizard tires feature beveled leading edge dual
row knobs in the center and well-spaced, siped
edge knobs to dig into loose corners. Designed
to be run on 50mm rims, the tires are tall and
wide, providing next-level traction and cushioning.
The casings have been designed to be responsive
yet supportive, even in the heavier 27tpi version.
Minimum rim size for these bad boys is 35mm.
ETRTO: 559mm
(note: designed for 50mm wide rims.
requires minimum of 35mm wide rim
to safely engage bead hook)
Casing: 120tpi folding bead (TBD)
27tpi wire bead (TBD)
I seem to remember that you had an oregon frame some time ago. The surly 29 x 3 easily fits in that frame with plenty of room to spare. Did you find any advantages in using the tire in an oracle frame as opposed to the oregon one?
Andre
The Oregon is more than just a very wide frame, it is also a very wide hub, so it has a different feel than a narrow hubbed muni and it weighs a fair bit more.
I found that the 4" tire was fun, but not necessary, so as the novelty wore thin I found myself riding the Oregon with narrower tires that would work fine on a regular muni, hence the trade of my Oregon and the build of my Oracle 29.
The Oracle 29 frame is good for all “three” tires and wheels I’m running; the third wheel is a 26" that is under construction. I think that if the Oracle frame was made 1/2" wider, it would fit all foreseeable tires and wheels we might run.
My Oracle is very lightweight, that is what I like best
I have the Oregon! I’ll be getting a dirt wizzerd on order today 
So I got the knard in the mail yesterday. Courtesy of nurseben. Despite what others have said about the knard not fitting on KH 29 frame I tried it and somehow she fit! Though my wheel does need to be trued due to the small amount of clearance.
Maybe it fits because of NB’s modifications.
I trimmed all the knobbies on both sides long the outside edge, it was a pita, but it was the only way to make it work on a narrower frame. So yeah, that’s probably why it fits 
You may still get a little rub if the clearance is really tight, such as when cranking hard and the rim flexes. Lower pressure will make it smaller…
I’m just glad I did not need to buy a frame just to run this tire. 
Has anyone actually tried a surly knard 29x3 on a standard (non-custom) triple triton frame? I can only find “maybe” and “maybe not” answers, but nothing definitive. Since the frame fits up to a 26x4.0, the width shouldn’t be a problem, but rather the height. A “fat” 29er might be cool, but I don’t want to invest in the wheel only to find that it won’t fit my frame.
Anyone out there with first-hand experience?
26 x 4?
It might.
But maybe not…
Haha thanks. That was the definitive answer I was looking for.
Oops. I forgot my winky-face.