After seeing video of Abram Clark’s 2:1 Penguin, I’m really interested in making one at some point in the future.
My question is this:
What’s the best giraffe to start with and modify for this project, price being an issue?
Would a Torker TX be an acceptable starting platform? Cut the arms off the bottom of the crank housing and re-weld as low as you can above the tire, then swap out the gears and re-chain?
Is there something I’m missing for how to go about it?
Thanks,
Chris
You could start off a BMX or an old b*ke. Then you just have to weld a seattube and make the wheel fixed (you can weld the freewheel and it’ll be fixed).
I’ve never built a Penguin unicycle though, but I’d like too:)
No input? Really?
I’ve heard a few mentions of penguins around here just lately… How does a penguin differ from a giraffe, just out of interest?
It’s not as high, and it goes really fast! The penguins unis are made to go fast, they have a bigger chain ring than the Cog at the wheel so it makes it much faster than any normal giraffe.
here is a video that shows the penguin’s performance:
Is it still considered a penguin when the axis (or should it be “axi”) of the pedals is below that of the wheel?
There was one at BUC this year, on a 26" wheel, each crank on its own axis, pedals at the normal height of a 20" wheel, with a gear ratio of about 2:3. It did have a couple of small problems: at such a short distance between the crank axi, and the wheel axis, the slight slip in the chain was noticeable; and when cornering tightly at speed, the pedals clipped the floor.
That’s called a Huni-Rex, it’s a brand that has since gone out of business but now sells its overstock for cheap
I wonder if someone else would ever sell a penguin
Penguins are fun. I built this one two years ago from scrap metal as an experiment. Shortest possible 20er giraffe unless I were to start cutting into the bb shell. In that picture it’s geared 32:20 making it into a 32er ratio wise. I later built a wheel for it with a 6 bolt 16tooth cog which makes it ride like a 40”. It has a chainring or cog eccentricity that makes it rather unpleasant to ride with the constant fluctuations in backlash. For that reason it sits in my closet until I feel like messing with it again. I have a couple clips of me riding it when it was 32:20 and a couple clips of some cal poly unicycle club members riding it as 32:16 although I’d have to figure out how to get them formatted in a way that the forum will allow me to upload.
Ah that brings back memories… over 40 years ago I built a penguin from a then 20-year-old 26in single speed bicycle that had been given to me much earlier as a Xmas present when I was 11 years old.
Basically, I cut off pretty much everything on the bike, and so I had a bottom bracket (with front sprocket and cranks) which was still attached to the rear fork (with rear wheel, chain and rear sprocket), and a seat tube (with seat post and seat of course). So, I welded the seat tube onto the bottom bracket, so it was then in line with the rear fork.
That was almost a rideable penguin, but it needed a smaller front sprocket and some welding to stop the free-wheel mechanism (I can’t remember how I did that) and a bit of cosmetic work to plug up spots on the bottom bracket where tubes were cut.
Then it was rideable! Free-mounting starting with foot on wheel, then pedal - hooray! It would have been nice to have some sort of tension device added to reduce the chain play, but I never got around to that. About a year later I wondered what it would be like with the original gearing (maybe I could go really fast?), so I put back the original front sprocket (more welding). Unfortunately, that was a stupid idea - it was unrideable (for me, anyway) with gearing that made it something like a 78in wheel!
So, it then languished in the garage for a few years as I couldn’t be bothered to do the work to get the smaller rear sprocket back on, then it sadly made its way to the dumpster.
I love these big chrome dinner plates. I’m not sure if I’ll do a 12” giraffe or a small tall b*ke. An 11” 65t chainring would look funny with a 12” wheel in either case.
They’re about the same size and I want to pair it with a 15tooth cog to gear it up to a 52”
I’m fascinated by this DIY “penguin” unicycle! Do you need to find a 20 inch tire kid’s b!ke that is a single speed, or will ones with derailleurs work? I figured the rear dropouts would be what I wanted and that is usually with the cheap backpedal-to-brake bikes with one gear. Can you typically use the top tube or down tube for the seatpost?
I’m not (yet) that interested in going fast. I figured that gearing it so that it was equivalently a 36” tire would be what I was going to try for.
That’s a cute… Beetle!
Holy thread resurrection
All curtesy of Sir_Twiggus from the unicycle discord
I don’t know about using a coaster brake hub or a derailleur but you could weld the bottom bracket to the front forks and cut everything else, then use a fixie hub
