Unicycle?
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Unicycle?
Anyone built a unicycle? I have a buddy that is looking for help to build a custom unicycle. I can get my head around most of it. I imagine using a MTB for crown (pacenti most likely because it would look awesome) and a straight gauge 28.6 .058 wall tube and a 25.4 seat post. I'm unclear on the dropouts. I found these https://www.unicycle.com/nimbus-raw-...e-bracket-set/ but would like some confirmation that they would work. I'm also trying to figure out how to use my fork jig and these dropouts.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
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I gave away my unicycle, but I think that's what the dropouts looked like.
You would want to avoid distortion as there is no way to true them up afterwards.
You would want to avoid distortion as there is no way to true them up afterwards.
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The linked hub bearing clamps look more substantial then the usual stamped steel ones then the common/low cost unicycles use. This is good.
I have thought about making my own unicycle for years. I bought a hub and bearing unit a long time ago but never took the next step. One trick I thought of to insure wheel alignment was to have the blades two different sections of tubing. The .058" wall with .125" smaller tube as a sliding fit thing. Join one blade completely and slide the other about till the rim is centered. Then join that blade. The smaller tube would be joined to the bearing clamp. The .058 walled and .125" larger diameter tube joined to the "crown". Of course this means a segmented crown. I'll also suggest that the bigger the post is in diameter the better it will stay put (without drilling for a bolt through the "steerer" and post). Consider slotting the "steerer" in two places and using a split collar to secure the post. Andy
I have thought about making my own unicycle for years. I bought a hub and bearing unit a long time ago but never took the next step. One trick I thought of to insure wheel alignment was to have the blades two different sections of tubing. The .058" wall with .125" smaller tube as a sliding fit thing. Join one blade completely and slide the other about till the rim is centered. Then join that blade. The smaller tube would be joined to the bearing clamp. The .058 walled and .125" larger diameter tube joined to the "crown". Of course this means a segmented crown. I'll also suggest that the bigger the post is in diameter the better it will stay put (without drilling for a bolt through the "steerer" and post). Consider slotting the "steerer" in two places and using a split collar to secure the post. Andy
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AndrewRStewart
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Kim Woodward
Post the build. I've thought it would be fun, but have not even gotten this far in the planning stages. I like Andrew's thoughts for alignment quite a bit!
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I have considered building a unicycle as well, including the Nimbus brackets you mention. It looks like blades using these brackets transition from round to ovalized and pretty narrow at that. The brackets are listed at 22 x 42 x 12 mm. I always took that to mean 12 mm wide. Not a lot of real estate to work with. I have never found a straight forward method for ovalizing tubing (that still looked good when I was done) to this extent without a lot of effort. I have pictured machining some unicycle specific hooded dropouts to account for this (that would allow use of round tubing or unicrown bike fork blades) but have not pursued it. I would love to see how you have progressed on the project.
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Thanks, that is a concern of mine as well. I'm realizing that standard fork legs won't work well. I was thinking of ovalizing the tops of some straight 4130 to fit the 30x16 fork crown. I think that works out to a 22.2 OD tube (plus filler). If someone could check my math here I'd appreciate it. I'll need the dropouts in hand to figure out the bottoms. I'm guessing some level of ovalizing will need to be done there as well.
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
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I used an online calculator to find that an oval with 30x16mm has a circumference of almost 74 mm and a 22.2mm circle has a circumference of almost 70mm. Of course, you aren't going to get an exact oval
I didn't follow why you don't like fork blades, how about a disc blade?
I didn't follow why you don't like fork blades, how about a disc blade?
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I used an online calculator to find that an oval with 30x16mm has a circumference of almost 74 mm and a 22.2mm circle has a circumference of almost 70mm. Of course, you aren't going to get an exact oval
I didn't follow why you don't like fork blades, how about a disc blade?
I didn't follow why you don't like fork blades, how about a disc blade?
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I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
I'm not one for fawning over bicycles, but I do believe that our bikes communicate with us, and what this bike is saying is, "You're an idiot." BikeSnobNYC
Last edited by Cynikal; 10-31-22 at 09:14 AM.