I’m the bike guy at the local hardware store, and we have a Raleigh chopper that my boss is willing to sell off cheap because of some defects. It has a Sturmy Archer 3 speed hub, SRF3.
Has anyone ever turned one of these into a unicycle? I know it has been done with some shiftable bike hubs, but what about this one? Does anyone have any clues as to how to do this?
I’m looking at using the hub to make a shiftable short giraffe, but I have no expirience. I know a couple of guys who can help me make a frame, but I’m more worried about stopping the coasting function of the hub.
I can get the whole bike for $100cdn. It retails for $320 at our store.
I’m sure I’ve read a thread or two that mentioned geared hub giraffes. I believe someone even has a set of instructions for modifying a geared hub for unicycle use, but I believe it only applied to a certain hub… I’m trying it on the forum, but no luck yet.
I found the instructions… but it makes the 3 speed hub into a two. I would like to keep all the gears. Maybe I’ll just buy it and find out for myself, it just seems like a bit of an expensive experiment.
Are you sure you want to freewheel on your giraffe? I’m pretty sure you need to freewheel to shift gears on those things; one of the reasons we don’t see more of them on unicycles. I’m not 100% sure of this though, so continue researching.
You are correct John, on most if, not all three speed hubs you need to coast to shift. If you shift while you’re pedaling it won’t shift until you ease off pressure on the pedals or stop pedaling altogether.
Don’t listen to the nay sayers. A free wheeling hub on a giraffe sounds like a great idea. You could coast like a mad man. Most important thing to do is document on video each and every step of your progress. We want to share in the experience with you.
Well the company says you need to ease the pressure. But there is no way I want to freewheele a giraffe. I can’t even coast or glide on my 24, and I’ve only ridden a giraffe once.
Well, it is apparently possible to stop it from freewheeling, but I believe it becomes a 2 speed. (according to sheldon brown)
Thanks for the info, I wanted some feedback before I spent the $100.
The last I heard these hubs were really rare and expensive, so if they’re being made again that’s good news! I also read about some guys that put one into a unicycle, not sure if they managed to fit cranks to it. the one thing I DO know is that they’re fairly complex inside, and if you end up disassembling it be careful cause there’s lots of weird little junk in there!
One minor frame defect and a couple of dents in the fender. Otherwise it is in excellent condition.
I guess it wouldn’t be too bad even if I had to dismount to shift, if what you guys say about needing to stop pedaling to shift is correct. I just think it would be cool to have… I wouldn’t mind a giraffe anyways.
The problem I’m finding with a lot of these hubs is that they are 40 spoke hubs. I don’t seem to remember seeing a 40 hole rim… ever. Plus the hub at the store here comes as a wheelset. I would have hub, spokes, rim and tire all ready to go. Buying a hub on ebay… they start at about $40cdn plus shipping, then I have to get a rim and spokes. And as I mentioned, I may have trouble finding the rim, unless of course I find one on ebay or something… the cost adds up fast.
The question I have asked is if it is possible to adapt a freewheeling hub to not. This is an opportunistic deal, I don’t think I’m going to go out of my way to order a hub and other parts. Maybe no one, or at least no one on the forum can answer my question.
There is plenty of information about these conversions on the web (and in previous threads on this forum). A three-speed Sturmey Archer hub can be converted into a two-speed fixed, or a four-speed hub into a three-speed fixed. The conversion takes a bit of effort and skill though. Have a look here http://www.hadland.me.uk/fairbrothersa.htm for one description of the conversion. There are plenty of others around if you search for “sturmey archer fixed conversion” on Google.
It’s probably worth a try if anybody feels like making one, but all the descriptions I’ve read mention a degree of slack/backlash that might make it unsuitable for a unicycle.
> I found one earlier today on Ebay.
>
> The problem I’m finding with a lot of these hubs is that they are 40
> spoke hubs. I don’t seem to remember seeing a 40 hole rim… ever. Plus
> the hub at the store here comes as a wheelset. I would have hub,
> spokes, rim and tire all ready to go. Buying a hub on ebay… they
> start at about $40cdn plus shipping, then I have to get a rim and
> spokes. And as I mentioned, I may have trouble finding the rim, unless
> of course I find one on ebay or something… the cost adds up fast.
>
>
> –
> madmattunipro
>
> ><>Unicycle For Christ<><
>
> www.bedfordunicycles.ca
>
> http://www.norco.com
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If you have the ability to build a wheel you can build a 40 hole hub
into a 36 hole rim. You miss two opposite holes on each side of the
hub. The spoke length remains the same but lace it up very loosely.
It will tension and true with no problems.
I converted a SRAM 3 speed to a fixed 2 speed and installed on a 5 foot giraffe this spring. The SRAM is suppost to have a lot less slop in the gears (about 1 degree). Still very difficult to ride at first. See the article Converting the Three-Speed Sram Torpedo Hub to a Two-Speed FG Hub
by Graham Webster.
