26 Carbon Guni Wheel Building

Unicycles and Equipment
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So I’ve got the chance to get a used Schlumpf hub, which I simply cannot refuse. I decided to build a wheel around it. The only compatible frame in my collection is a KH26, so a 26" guni it will be. The guni will be ridden mostly on an urban road (for commuting), I’ll keep the original wheel if I need to convert it back to a muni.

Components of the wheel is more or less determined, but I’m still posting them here in case I’ve made some bad decisions. Any input is welcome!

The rim is from Nextie. Despite some of us had an unpleasant story on their 36" rims, I think for more regular rim sizes their products are reputable and reliable. The most important thing is, they can make it 36-hole. It will be a carbon wheel, 40mm wide (31mm inner). 550g.

As the rim is hookless (can’t really find a hookful 26" rim), I’m gonna put a foldable Maxxis DTH tire on it. The tire has 2.15" or 2.3" width, I chose 2.3" for better stability. It also has the EXO option, but I reckon I won’t like the look of the tan wall paired with the blue KH frame; plus I probably do not need its extra puncture protection on a city road. It weighs 650g. Paired with a tried and trusted Maxxis Ultralight (0.6mm) tube, weighed at 127g.

Spokes will be Sapim Race steel double-butted, nothing fancy at about 200g.

Theoretically the wheel will be around 3000g. Not really light as the Schlumpf hub is super heavy, but it does not contribute much to the rotational inertia, so I’m pretty looking forward to its performance.

To complete the wheel there still has to be the cranks, the pedals and a rotor. For the cranks I’m thinking KH Spirit 117/137 double hole, but could it be too short for a guni? I also would like to try carbon pedals (with titanium axle). There aren’t many discussions about them here, does anybody have experience with them on a unicycle? Are they durable, do they worth the money?

Again, much appreciated for your input!

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I’m not sure of this but check to see if you should use a double butted spoke in a carbon rim, I’ve heard that is not good. Hope I have heard wrong because I like them as well.

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Why carbon pedals on a guni ready to UPD? Isn’t it more easy to buy nylon ones? Does exist a nylon+titanium axle pedals?

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Can you find a reference for that? I searched our site as well as the internet, but failed to find anyone complaining about it. Double butted spokes are widely used with carbon rims on bicycles, is there a unicycle-specific problem?

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Yes, nylon might be a better choice, A brief search shows Litepro makes them (titanium axle + nylon):
https://www.walmart.com/ip/LP-Litepro-Titanium-Axle-Bicycle-Pedal-Nylon-Material-Bike-Pedals-3/1177520770

Is it because carbon pedals are prone to break on UPDs that you don’t recommend them?

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From the Light Bicycle build manual that is shipped with their rims. Butted spokes is a good choice.

IMG_20221206_221603
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Nylon pedals won’t crash in an UPD. I own a pair of 100€ pedals which are same weight, more fragile and less grippy than a good pair of nylon cheap ones. The nylon are on the Uni’s cranks, the alu special ones are on a display (and maybe I’ll put them on sale)

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Hi hillin, I believe I got that notion on not using double butted spokes with carbon rim from an earlier post on building a carbon muni rim. Maybe the fact that they mentioned using straight gage on the drive side for mountain bikes and disc side for muni. but I love the look and don’t care about weight one way or another. Carbon rims are not my expertise. My experience with carbon fiber is in the hypersonic aerospace world.

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True, nylon pedals never dissatisfies. I was just tempted to try something fancy :wink:
Guess I’ll give the ti-axle nylon pedals a shot.

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Yes, I confirmed with my rim dealer, they said any kind of spokes will do just fine. Guess I’m safe with the butted ones.

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Hillin, Thanks for the research and clearing that up for me.

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I would dare guessing that most “carbon” MTB pedals would also be nylon - just reinforced with carbon fiber instead of the cheaper and more common glass fiber. At least that is the case for the few pairs I’ve found searching.

For Muni I’ll continue to be a fan of aluminum pedal body and steel spindles. For a road uni nylon and titanium is probably okay, since it isn’t under high stress from drops and doesn’t hit the ground as often. From an engineering perspective titanium spindles always seem more like a marketing driven solution than the most sensible way to save weight, but that’s also just me being nerdy.

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I might be selling my Schlumpf carbon 26er sometime soon. Such a beautiful machine but I’m closing in on 70 and haven’t been riding it much lately.

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mmexport1675385192178
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The wheel is built, can’t wait to ride on it!

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MVIMG_20230210_071418
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Here it is!

First ride today, the high gear feels pretty funky, still need (a lot of) time to get used to it.

Just a quick question, is it normal to have a slight click feeling at the hub with every rotation, no matter on low or high gear?

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That looks rad.

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My hub does that when I am pushing it along. After much listening and trying to work out what it actually is - I have decided I’m hearing the play in the cranks as they roll round and gravity tugs them down on each roll round.

When riding I don’t hear any click but the play (forwards and backwards) is 100% normal.

Only other thing to check click wise and I check pretty much every other ride - is that the shifting buttons aren’t too loose - and that they’re not too tightly wound into their spaces or too proud. You want each button to be slightly spongy/springy when that button is engaged in.

If tight I suspect it could cause some kind of click.

And re your new ride: wot Ryan said - very nice set up! :gear::star_struck:

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