Surly 24 x 4" Conundrum: As it was meant to be

When Surly first offered the Comnundrum in a 24’’ and 26", they paired it with a Large Marge rim DH version (no cutouts), but only a few fat tires were available at that time and they were all for the 26" rim, so the 24" frame languished…

Fast forward five plus years, fat biking has gone mainstream, 26" fat tires are a dime a dozen, but only recently has there been a “mini fat” bike for the little people. The availability of these smaller fat bikes, rolling on 24" wheels, made this muni possible:

I still need to add the, NB Grab, the D’Brake, and the Spyke caliper/Speed Dial lever, then we’re ready to ride. On it’s maiden voyage last night it was awesome! Super cushy, agile, so comfortable, and it didn’t feel like a 24" muni.

Tire width was not qiote as advertised, it’s closer to 3.25" in width, height is right at 26". Specialized has a 24" tire that may be a little wider, but the price was really high ($200 for the 120tpi), so I’ll wait until they “sober up”.

The tire went tubeless fairly well, I used a bungee to compress the tire, a compressor to get the initial seal, 20mm Stans tape covered the center perfectly, presta valve, but the rim is a leaker!! I was abel to get it to seal, but it kept leaking through the seams at the sidewall, so I expect that I’ll either do a split tube or a full width tape once it leaks down.

The Build:

Surly Conundrum 24", Champagne
KH Zero Seat and Post
Salsa Post Clamp
Nurse Ben Grab Handle :slight_smile:
KH Spirit 127/150
Nimbus Chromo Hub, 14ga straight spokes
Nimbus Stealth 2 rim
Nuke Proof Electron pedals
Chao Yang 24"X4" 120 TPI Tire, Tubeless Stans Tape, Stans Presta Valve

And yes Dorothy, it’s worth it :slight_smile:

My beloved NB Handle is resting in the box you shipped it in because my 12 year old daughter has taken over my 26" Oracle and she prefers the built in saddle handle. Let me know if you want it back free - shipping. It served me well but I’m getting along with a shortened T-bar on my zero on my KH29.

Sweet looking Surly dude! My 10 year old son is still vertically challenged for her Oracle. I was thinking on a 24" for him and he’s already grown accustom to a fatter 19" trials tire so something like your 24+ would certainly fit the bill. I’ve never owned a 24" uni. I’ve been working my way down from a 36G. :sunglasses:

If Nurse Ben doesn’t want it back, I might be interested. :stuck_out_tongue:

:astonished: :astonished: :astonished: now, that’s going to be interesting!
Can’t wait to hear about how it rides.
What’s the inner width of the rim?

Sweet. :slight_smile: I’m in the same boat…just waiting for the 24" Fat Ground Control to be discounted.

Real neat.
Since it’s less than 4", would it fit in a regular 24" frame? Like a pre-2015 KH?

Yeah, I’m thinking the same thing - my Torker DX has a ton of clearance, and steel tubing that I wouldn’t be afraid to “ding” in the right spot for another quarter inch on each side…

The rim width is 45mm ID, standard issue Nimbus rim.

Tire width is ~3 3/8", it’s new so it’ll probably stretch to ~3 1/2"

I have no idea if it’ll fit in a KH frame, the tire is wider than a Gazz 3" which is a tight fit.

The diameter is a solid 26", so you need crown clearance as well.

I like this size, it doesn’t feel too small, and it is super agile. I think it’d be neat with a Schlumpf :slight_smile:

What we need is a new batch of Surly frames!

I’m hoping that UDC is paying attention, they have a lot to gain from “re-starting” the 24" wheel size, and the availability of these 24" fat tires is improving.

I think there are three brands building 24" x 4" tires

Chao Yang (Framed Bikes)
Vee Rubber (On One)

All yours, I have a couple, and I’m working a new design :slight_smile:

Me, too

Dammit! You’re always one step ahead of me. I have a 24x4" Mission waiting at home that I’ll put on a Conundrum this weekend.

I’m still sold on my 650+ as the Jack of all trades go-to uni, but I could see this being a ton of fun. I think I’m going to forego a brake and just makes this about simple fun.

Though now that you mention it, a NB grip could really help to throw it around where I want it.

Planning on running a 24x4 wheelset on my next frame (along with a few others). I’m a bit disappointed to see that the tire came in way undersized.

Where can you get a 24 inch rim by itself? I haven’t had much luck in finding one. Conundrum frame is on its way, but it’s probably going to be a 26 because of that. : / has 24" 80mm wide rims w/36 holes for $85. They also have a 65mm rim which would be similar to the Large Marge. All of these are double walled. I have no experience with them, but for a while they were the only option to a Large Marge which lead me to think that maybe they were being sourced from the same factory. Anyway, it’s an option.

This wouldn’t work for a 4" tire. Even if it did it wouldn’t fill the tire out. I already have a Nimbus 24 muni…and I’m not buying from anymore.

I’ve been noticing nobody seems to have rims with reinforced eyelets for fat bikes. There are a couple out there, but even the surly rims don’t have eyelets. Is there some reason for that? I had looked at the origin8 rims on jenson as well. Again, double walled, but no eyelets.

I’m leaning towards a KH rim, which just barely works with a larry tire, but I would prefer the old large Marge rim. I’ll keep choppersus, but if I’m planning on doing muni with it and not just smooth sand/snow, should I just pony up and get something like this:

yea, they aren’t 24" rims, but I trust the 26" options a bit more. The conundrum could fit either.

I would send choppersus a message asking about the metal the rim is made from. I wouldn’t discount it so quickly. After all KH doesn’t make rims, he has them made. Of course he specs them and is the last word on the QC, but Surly and ChoppersUS are in the same boat in that regard.

As for eyelets, they were originally used to eliminate the need for nipple washers. So if you feel like you need them you can always use washers. I always thought the washers did a better job than eyelets anyway, but they do add a slight bit of weight. I think single eyelets were used to make rims faster to build. If you go with washers they will add slightly to the erd. They are very thin stainless steel.

Actually I take that back. Clearly it works from the original post, but it takes width off the tire considerably.

I have no clue what that would do for the footprint and stability, but most of the big tires are designed around a fatter rim, so I imagine running a 42mm rim with a 4 inch tire probably isn’t ideal, but could work.

Ahh I didn’t realize that was a thing. Knew about the ones for hubs, had no idea there was a similar thing for rims. I’ll probably go with choppersus then. Thanks.

Yep, but I can’t blame you for not wanting to buy from udc.

I went to and I was able to see the Ground Control Fat tire listed in 26x4.8, 24x4.0 & 20x4.0.

Only the 26’s price is $120 the other two are $40. I even managed to place an order for one (see attached screenshot) and it went through. That’s true there is no details about 27tpi/60tpi/120tpi but it is a better price than the $70 (w/o shipping) that I found for the Chen Yang tire on eBay.

Let’s wait and see :stuck_out_tongue: