Apologies, but I am not up to speed on all the details here. Why can’t you simply mount this 20" Mobo wheel on a 20" unicycle frame with 40 mm bearing houses 100 mm apart? Why the chopping or bolting straight through (what exactly?)?
Because the mounting is not for standard 40mm bearings.
There are two discussions going on at once in here so perhaps that’s where you’re getting mixed up.
The Mobo wheel has mounts already on it, over the bearings, and one assumes that this is necessary (at least on one side) as it’s part of the shifting mechanism.
It’s probably also not 100mm spacing, and honestly I wouldn’t be massively surprised if it’s something weird and not 40mm OD bearings.
This conversation is making me want to have a poke at my back-pedal brake freewheel again. It’s still totally unrideable due to the amount of backwards play it has and I need to wrap my head around exactly how it works so I can figure out how to tighten it up! It may still be unrideable following adjustment, but I’d like to try.
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Thank you! That was clarifying. If I were to make my 16" unicycle a freewheel I would have to replace my hub with this Cottorless freewheel hub or build a new wheel around it.
I think that would be a spectacularily bad idea though. I guess building a 20" wheel makes more sense 
Haven’t there been unicycles that had the same mount for the lollipop bearings and flat bottom ends on the frame? I don’t remember what brand it was, but I’m sure @johnfoss will do. I’m sure you can still find those used and cheap.
Most lollipop bearings I’ve seen (and owned) have been aluminium castings which go inside the frame tubes.
I just went and counted the spoke holes and indeed it is 32h. I should have done that in the first place.
Other than that it looks like the Nimbus hub
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The one in this post looks like it might fit.
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With the Mobito wheel I would’ve tried to fit it to my Amazon special Though with the relative lack of info with the Mobo wheels and the fact that some fabrication is probably required (and I’m not too brilliant with fab yet), I decided to opt for the High Roller hub.
I’ll probably build a 26" wheel around it and use it with my Club frame… Which also means riding brakeless 
I’ll probably go with a rim-brake compatible rim in the event that I do decide to either get a frame with rim brake mounts or figure out a solution to put them on the Club.
Maybe at some point I’ll revisit the Mobo wheels and get one myself, though that will be further down the line. I was hoping with the Mobito 16" wheel that I could just pull off the bearing housing on both sides, replace the bearings with the cotterless 40x17x12 bearings if needed, and drop it into a unicycle frame. I suspect though it won’t be as simple as that though, since it’s likely best to assume it won’t be a standard bearing spacing for unicycles 
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From what I can see your Club frame should take 40mm bearings so that should be fine with the High Roller hub to just drop in. If you do need to shim it to 42mm at any point (for another frame) you can get shims from UDC.
I’ve updated the initial wiki post in this thread to correct a few bits/add more information, as well as to add the Mobo shift, and the Huffy Green Machine (back pedal brake).
I’ve emailed Mobo to see if they’ll send just a hub to the UK as their website only lets me select the USA for shipping, and I don’t really want/need another cheap wheelset
If they can’t ship direct, but can sell me a hub by itself, who in the USA could act as a middleman for me?
The High Roller hub came in today… And it fits like a glove!
Now I just have to decide what kind of rim I’ll want to build around it… Initially I was just going to make it another 26 inch wheel, much like the rim that’s normally installed on this uni.
I’ve also built a skinny 700c wheel, but with barely any clearance even with a 28c tire I’m not sure I want to compound the difficulty of a freewheel with the twitchiness of a skinny tire.
Maybe I could build something in the middle… I’ll have my regular 26x2.125" (57mm) wheel for all-purpose riding, my skinny 700cx28c wheel for some nice smooth road riding, and perhaps a freewheeling 650b with a road tire somewhere in the middle? What do y’all think?
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It sounds good for the road. I would prefer the 650B.
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Until recently I had 2 nimbus drift trike hubs. I don’t need them anymore, since I have 2 Pipifax hubs.
I’ve just sold one nimbus hub as spare parts and want to check the other one before selling a whole wheel.
I am wondering if anyone has ever made a video of the assembly/disassembly of this hub or a similar hub. 
On the 2 hubs I’ve had, none of the bearings fit easily by hand (either the 2 internal and 2 xternal bearings on the axle, or the 2 internal bearings into the hub body).
If someone has already done this, can you confirm that the pawls and the inner bearing must first be fitted on the side opposite the pawls, before inserting the axle into the hub body by passing the pawls through the hub body from the opposite side (to the one with the pawls)?
I remember trying to insert the axle the other way round, but I ended up having to force the internal bearing into the hub body on the pawl side, even though the pawls weren’t in place… which made it impossible to continue. 
Thanks!
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I took apart and reassembled my Nimbus hub back in the day and I seem to remember you just spin the axle around and the pawls will retract and seat themselves back into the ratchet ring, indeed my notes on the hub in the first post say similar:
To do this, the non-clutch (disk) side circlip is removed, and the axle can then be lightly knocked out from that side.
To re-install, spin the axle in the freewheel direction while re-inserting and the pawls should automatically retract and slide into the hub shell, then reinstall the circlip.
I understand that you reassembled the axle in the hub body without the internal bearings.
In this case, I have the impression that it’s complicated to keep the axle in the right position while fitting the first internal bearing.
Thank you, I’ll get back to you when I’ve succeeded… I believe it!
No, all bearings were in place aside from the disk side frame bearing (as it has to be removed to get the axle out).
The axle, with pawls and bearings still on (hub and frame bearing), is spun in the freewheel direction as reinserted into the hub shell.
You can’t access the pawls as you do it, but they retract and go back into place (or at least they did for me the few times I did it).
Okay! That’s it! I’ve changed the pawls, the spring and greased the hub thoroughly.
I proceeded according to the method I had been thinking about. I took step-by-step photos so that others could use them.
The tools you need :
- 22.2mm tube
- hammer
- bearing extractor
- circlip pliers
1/ I first disassembled the 4 bearings.
2/ It is absolutely necessary to remove the 2 inner bearings from the hub, otherwise it will not be possible to fit the pawls.
3/ I fitted the pawls, the spring and mounted the bearings on the axle opposite the pawls. I preferred to mount the outer bearing and the circlip to ensure that the inner bearing don’t move on the axle during assembly.
I didn’t go easy on the grease. In fact, I got it all over me, including my phone… but it makes assembly much easier, and it’s not bad for bearings, which don’t have an unlimited lifespan.
4/ Then comes the most important step: folding the pawls into place.
I tried to push them in by turning in the direction of the freewheel, but it didn’t work, so I simply used my fingers to fold them over and insert them from the opposite side, passing them through the hub.
5/ Once the pawls are folded, simply push by hand and finish by using the 22.2mm tube and hammer to insert the inner bearing into the hub. Of course, when installing the bearings, the other end of the axle must be placed on a hard surface. I put the axle on my workbench.
6/ I added more grease to the pawls, and then installed the pawl-side bearings and the crank.
To fit a disc, you have to remove the external bearing fitted at the start, but fitting it seems to me to make things much easier later on.
I can’t see any other way of doing it, but it’s great if others can do it differently. In any case, I’m very happy to have finally done it. 
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Going back a few posts because @MrHydra just posted a project update on his freewheel build on the other thread…
How viable is a brakeless freewheel unicycle for someone (like me) who would be learning from scratch to freewheel on it?
Next step along, how much better to have a Magura rim brake?
I may have found someone willing to part with the hub of an old Huffy Green Machine drift trike, and I have possible 20" and 24" frames with wheels but no brake mounts, and also an old chrome 26" Nimbus II frame with Magura mounts but would need to find myself a Magura-compatible 26" rim (and an old Magura setup from someone).
The potential hub donor is actually a much better unicyclist near me who would probably be first to try to learn freewheeling on anything I created (and who actually has braking proficiency, which I don’t really), but it’s a question of trying to create the most viable low cost fwuni from what I’ve got already or could get cheaply on auction.
I’ll also be going into (brakeless) freewheel unicycling without prior experience… Hopefully not head-first 
I know it’ll be extraordinarily difficult, especially considering I don’t have much of a “skills” background. Despite that, I’ll try to give a good effort practicing once spring rolls around and the snow clears up. I don’t fully expect to be proficient at it any time soon, but at least I’ll have some exposure to it.
As a freewheel rider myself that is riding with a disc I think that by beginning brakeless might make you a better rider in the long run but at the start I think you will get hacked off with not actually getting much riding time in before falling off.
I’m about 2 years in and I can ride without using the brake but it’s always needed for quick recovery to prevent offs.
I think it also depends on where you plan to ride and what’s your goals.
Perfect smooth ground like sports halls you’d get away brakeless maybe but Muni or trails you will want a brake.
Just my opinion as a freewheel rider that has been putting as much effort in as I can.
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