Plethora of fat tires, time for some more fat frames?

Fat biking seems to have just taken off in the biking world. are we going to be left in the dust?

A lot of the earlier adaptors were turned off by the slow handling and square profile of the Endomorph tire. 2 years ago Surly introduced the Larry tire which changed things significantly but we still had very limited choices when it came to tires.

In the last month or so the number of choices have almost tripled, with offerings from Surly as well as a couple other companies.

We started off with the infamous Endomorph 26x3.7, a high flotation tire with square profile and low tread

Then came Larry. Larry changed the fat biking world by giving a fat tire a rounder profile and decent grip. Designed to be a front tire it also works well as a unicycle tire.

Using the same carcass Innova released the Spider 4.0 tire. Meant primarily for fat beach cruisers etc. Not too much is said about this tire, it is generally a cheeper alternative to the Surly branded tires and has a perfectly round profile.

Then Surly did the unthinkable, in an areana that had only a couple tires they went and offered a bigger fatter tire for more float, a chunkier more aggressive tire, and a nice smooth road tire for those rolling on the flat top.

I will start with the Big Fat Larry, or BFL. BFL is basically a bigger fatter Larry, as the name suggests. still the same pattern as the “smaller” counterpart but a little bit wider and miraculously lighter as well. It should fit in a Oregon frame but I don’t think anyone has tried in a Conundrum or Triton yet.
Big Fat Larry 4.7:

Next we have the Surly Nate, same size as the original Larry but bigger chunkier knobs for those who want big traction with the big tire.

And finally from Surly we see the Black Floyd. Another tire coloured piece of brilliance for those who want to ride the fat without all the knobs and rolling resistance.

Just when we thought we were done a couple more companies come out with some new fat rubber. North 45, another QBP company (Surly is owned by QBP) has also announced that they are joining the party with the Hüsker Dü. Looks like it would be great on a unicycle with more front back traction compared to a Larry but not as aggressive as a Nate.

And now it looks like V Rubber is also jumping on the band wagon with a 4" tire, and this looks to be the first fat tire that isn’t made by Innova. It is supposedly heavier than the other tires but should come at a lower price point.

Looks like a decent tread pattern.

With all these options available to us it might be time we get some more choice of unicycle frames to put them in. Of the tires listed I have only used a Larry but I think that the tires above have huge potential for downhill, XC, loose condition, and winter riding.

There is an explosion of new fat bike frames, will unicycles fallow their examples?

Thanks for the write up Eric.

If our frames get any wider we’re all going to look like bow legged cowboys when we walk. :roll_eyes:

Sounds like we need a “Fat Holm” KH frame to fit all these Fat Tires! :smiley:

+1 on the KH fat frame concept. My thinking: a frame to accomodate a 3.8-4.8" tire needs S curved frame legs to get around the tire and back down to the 100mm bearing width and flatter or ovalized tubing seems to help slim down the frame legs of the Conundrum, hiding the fact that the tire is so wide. I have a Big Fat Larry coming tomorrow that I’ll try out on my Surly Conundrum frame. I’ll let you know how it fits.

I think others might have already said it, but the fat Larry and Surly get more miles than any of my other unicycles combined and has almost put my 29er single speed into retirement

The strait legs on my Triton frame do OK but yes I would prefer an S bend on the legs. With the strait legs the tire clearance is about 104mm which is more than enough for my current setup of Larry on a 46mm rim but not so sure about BFL or a 70+m rim.

The strait leg also just barley clear the disk on my MU disk brake system with a standard hub, can’t quite make the disk + schlumpf work on my triton as the schlumpf puts the crank in just a bit further.

An S bend could allow more room for the tire as well as not complicate the disk brake setup.

If I could find a bigger fatter aluminum conundrum style frame that is compatible with a Schlumpf I would be all over it.


+1 as well! A KH PHat is a great idea Eric!

side note, I’ve seen Dmitry is making/completed a Ti 29er B*** recently, so maybe a Proto Ti 26 that would accomodate a 4.0" tire is something we can bring up in casual conversation.

I think that was spelled C O N U N D R U M :roll_eyes:

Yeah, we do need some fatter frames to run these tires, but I imagine the unicycle market for such tires is small, very very small. So, for now we have the Oregon, the Triton?, and the Conundrum (if you can find one).

I already have the BFL mounted in an Oregon, it fits fine, plenty of room, next upgrade is a fatter rim so Larry’s bigger brother can s p r e a d o u t.

What would be really cool is a hydroformed frame like you get on some mountain bikes :slight_smile:

The 4.7 stated width for the BFL is on a 100mm rim. Have you measured its width on the 65mm Large Marge?

How do these big tires do in the mud? I read some good reviews for the larry, for having a good floatation on the mud. But most bike mud tires are very skinny, so they cut through the mud, onto the harder ground underneat.

I ride a 24 x 3 Duro Wildlife, which has a disapointing mud grip, but I like the fact that I can run it at 0.8 bar (12 psi). Does a Larry grip better in mud?

David, i already posted my review, search is your freind :roll_eyes:

The BFL is bigger than little brother, but more in overall size than absolute width. It would likely spread out on a wider rim, but that would take new wheel build. Sadly, the $$ just ain’t there with ski season coming on strong.

My son prefers the Larry, so the BFL will get light use in the interim or I might just sell it now that I had a chance to try it out :stuck_out_tongue:

Funny Bryce, but I rode the Orego a whole bunch last winter, then I started riding the 29er and it feels so fast that I’m not sure I want to give that up. My son calls the 29er a sports car to the Oregon’s burly 4x4 mannerisms.

Hey Tom, all tires slip in the mud, Larry included, so much depends pn the terrain. Larry floats and supports the rider better than a Duro 3", but it’s still just a tire. I’d suggest timing your mud riding to avoid sloppy riding or hit the mud when it’s cold/frozen. Snow, on the other hand, can’t be beat for Larry riding fun.

A more burly, ie deeply treaded Larry, might be interesting, but too much of a good thing is often too much, esp on a single wheeled uni.


So I picked up my Big Fat Larry this afternoon and installed it on my Surly Conundrum with a Large Marge XC rim.

First few pics are of the original Larry on the Conundrum. I measured the casing and found them to be about the same size: Measured from wire bead to wire bead, the BFL was only about 3/8" larger than the Larry.

The tires weigh about the same, with the BFL weighing a little over 2 oz more than the somewhat used Larry.

So I put the wheel back in the frame and pumped it up. 150 strokes on a shop floor pump and I was up at 25PSI and the wheel wouldn’t move at all in the frame - unless I lowered the pressure to 5 psi, then it barely clears the seat tube. The BFL is about 1/2" taller in the frame (so think 1" taller from bottom to top of the tire) than the Larry and the frame seat tube is now in the way. Bummer, yes . . . but I guess this is the result of unicycle industry begging at the heels of the bike industry for a scrap or two every once and a while. And the BFL looked like a really tasty scrap that I really lik-ee! So I radiused the frame seat tube with a grinder and electric band file following along the black lines drawn on the frame - and now it fits! The Magura four bolt brake mount corners come within 1/4" or so of the tire, but the sides have plenty of clearance.

But how wide is it? Installed fully inflated at 20 psi, from knob edge to knob edge, the BFL is 105mm wide (casing will likely stretch a bit more in the next few days) and the Larry is 94mm

Last pic is the BFL on the right and the original Larry on my snow bike on the right.

A quick ride around the neighborhood: BFL seems even better at absorbing bumps and curbs than the original Larry. The felt weight and road crown issues seems about the same at the 15-20 PSI range, but at lower pressures it seems evan better at gobbling up curbs and drops like they don’t exist. Worth its $128 price tag? Hard to say at this point.

Anyone taken BFL on a trip to the woods yet?











Is there any use for the 4", 4"+ tyres other than snow/sand?

If I was back in Colorado I would consider building an epic snow uni with the Larry or BFL. Other than that, wouldn’t want for for muni.

I’ve had the BFL in the woods, it does gobble up rough terrain nicely, tends to have an independent mind at times, not obviously heavier. I think the ride difference between the BFL and Larry would be equalized with a fatter rim, making the tire profiles more similar.

Bryce, bummer about having to modify the frame, I would have thought the clearance would be better. The Oregon has plenty of space, enough even for a tire even bigger than the BFL.

I’m looking to pick up one of those other tires, possibly the Nate or 45NRTH, just so I have a tire with deeper knobbies for when the Larry is a bit slippery.

Anyone interested in my BFL for a discount?

Hi Ben. See PM on your BFL,


yes - playa

I tend to reach for the Oregon/Larry when things get slimy/sloppy, which is during our winter time/rainy season. The fat tire is really great at maintaining contact, esp over wet roots and rocks. I don’t find it to be all that big, esp in comparison to a Gazz 3.0 and it’s certainly not any heavier than a typical 3" tire.

It does take more energy to lug about a fat tire on the trails, but that certainly beats slipping and sliding and the increased UPD rate if I ride the 29er on those same slimy trails :o

I think it’s a good thing to have in the quiver, keeps you riding when conditions are not uni friendly :slight_smile:

bump! any one ride the 45 north yet. i got a Oregon in the mail and was thinking about getting a 45north because i can get it cheep!

Where? I thought that they were coming out in December.

Just bumping this thread…

The tire choices are growing, but we need the frames to match. The Oregon is not a bad frame, but the legs are kinda wide. I Think the Oregon could easilly be narrowed and still have plenty of tire clearance.

One thing I’d add about “bowlegged riding” is that the current 100mm hub spacing running KH Moments is about the same pedal position as a typical mt bike, so no really wide at all.

If we had an S frame design like the Surly but with more clearance, that would be the ticket. I’d like to see an aluminum “hydroformed” frame like Specialized is building.

How much?

I am not working till the 3rd i think i will find out how much then. I am ordering a N26 after i get paid and after i sell my bike a oregon.