I wanted to ask everyone what your experiences are with carbon rims, especially for MUni.
I would like to optimize the weight of my fatty unicycles even more and there is no way around carbon. Single-walled rims are out of the question for stability reasons. Double-walled rims, 65mm wide, weigh just under 600g.
I am specifically addressing MUni drivers here. What are your experiences with double-walled carbon rims? Are they sufficiently stable? Do carbon rims have any “quirks”? Since carbon rims aren’t cheap: is the extra cost worth it?
Best regards Stefan
Saving a few hundred grams on the rotating mass helps you jump and absorb some bumps more easily. But some people may prefer heavier wheels, with more inertia as this can help roll on bump 
Carbon is also stiffer than aluminum so you can be more precise on where you put your wheel!
So, for a good rider, that’s totally worth the price. But for a beginner, that may not help.
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thanks for the reply. I’ll have a sample made and test it. My Fatty is equipped with a 45mm rim. Works without problems. However, with a width of 65mm I see the advantage that you can drive with even lower air pressure. It’s all just theory, practice will show it
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Alot of different factors come into play. I personnaly have a single wall rim on my Fat unicycle and it’s fine. I only use it in the winter on the snow though. 80mm wide rim with a 4.0 tire. Stability is no issue. But I hate the bigger tire in the summer (or on any hard surface). That uni has seen jumps and drops, but the landings are usualy soft or smooth (ish).
On my muni though, I have a Derby All Mountain carbon rim. I’ve had this rim since 2015, it has seen very rough riding in hard terrain. Plenty of big jumps and drops. I was soft on it when I got it, and now really I’m doing everything I want to ride. It’s strong, it’s stiff! But, it’s only 75g lighter than the alloy rim I had before. The riding is different though, since the rim is very stiff. It’s 30mm with (internal), and I have a 2.6 tire on it.
My personnal experience is more around the general feel of the wheel rather than weight since I already had a fairly light alloy rim. I would choose carbon again if I manage to break this rim I currently ride. It’s fun to save weight, but a stiffer wheel means it’s more efficient, meaning it’s more fun to ride (for me at least).
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thanks for the feedback. stability was my biggest concern. You write that you don’t like driving the fatty tires in summer. Have you already tried the following tires? : Surly Nate 3.8" (good MUni tire) Kenda Juggernaut Pro 4" (less tread, but extremely light and easy to steer). Maybe you’ll have fun with these tires in summer too.
My experiences with carbon rims for Muni are excellent. It’s all I ride now on my 27.5 and 26. I’ve built 4 wheels including my own. They’re very stable, strong and lightweight. They definitely make me faster on the climbs. Light Bicycle is where I bought mine. I have no regrets.
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I originally had a Nate 3.8, eventually switched to a 45NRTH Van Helga, both horrible experiences hahaha. The fat tire just doesn’t fit my riding style really. I like a tire I can feel and that steers fast, smaller tires do that. And I think it suits the carbon wheels well since that’s how you can get most of the advantages out of carbon. A nice stiff and responsive feel.
Stability has alot more to do with rim to tire width ratios and tire sidewalls. The material of the rim wont change much in stability.
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I recently built up a 29" Muni wheel with a Light Bicycle RM29C15 rim. The rim has a great build quality, and it laced up, tensioned and trued really easily. It required virtually no truing at all. Equalizing spoke tension with a tensiometer got the rim to within 1mm of true laterally and no hop at all. Using this rim saved my build 255g when compared to the KH 29" aluminum rim
I’ve only done light XC with it so far so I can’t comment on durability (though the mtb community rates them highly). But I’m otherwise very happy with it and wouldn’t consider building with an aluminum rim again other than for cost reasons.
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Now add a TPU tube, then it’s another 100-200g lighter.
I set it up tubeless and have had no issues. I’ve tried side hopping to see if I can get the tire to burp with no success.
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