In this thread there was a picture of a half-fork unicycle and from this forum, I learned for the first time about Cannondale Lefty. Shortly after I read that, my LBS had a Cannondale Lefty in the shop. I could not understand that such a construction could be stronger than a forked frame. My wife wanted to have a new saddle pin for her electrical bike and I had a talk with the store owner about the Lefty. He said it was very strong and stronger than a normal mountainbike.
Other than the picture from above thread about the unicycle clock, which I still donât know if it is photoshopped or not, as on of the pedals is stuck to a spoke, has anyone ever built a Cannondale Lefty unicycle, and if so, is a Lefty as unicycle just as strong as one as a mountain bike. Youâd put much more weight on the wheel than on a mountainbike and I still canât believe that with excessive force, like with a jump (hop) and faulty landing, the wheel might twist. What are your ideas?
As I like having multiple unicycles, a Lefty would be a welcome addition to my fleet.
Well I own several lefties,way stronger. But the problem is to come up with the hub/bearing/crank combination. The suspension would have enough give to help with any additional forces that you may think it would encounter. (I know about suspended unicycles).
LobbyBopster
If it was in fact a real uni, it was a one off (and Iâm 99.9% sure itâs just photoshop).
If I understand correctly, the lefty concept is only really benefitial when you use suspension forks (when you build a suspension fork, the leg(s) have to be relatively thick to house the spring/airchamber/dampener), so there is more of an advantage to going with just one leg. On a rigid fork you have much more design freedom, so I think if there are any weightsavings to be had from going to a single leg, they are much smaller.
As Lobbybopster points out, you would need a custom hub/bearing solution, which would be very tricky.
I think elite Mountainbike riders will put a lot more force on their forks than most unicyclists. The speeds they can get to will make up for them having twice the wheels to distribute the weight on, and even cross country mountainbikers do some super technical stuff.
I remember thinking how cool it would be to have a one-wheeled mountain machine with a one-legged fork. But if anyone ever made one, they didnât share it online that Iâm aware of. As mentioned above, it would have required a bunch of custom machine work to make it a uni. Based on the pictures Iâve just looked at (Google > Cannondale Lefty > Images), you would at least have to design and machine a hub to go over the existing axle. That said, you would have the option of a disc brake included in what Cannondale offers. 
The UNIPSYCHO lefty unicycle seems to be related to UNIPSYCHO: A Documentary about a unicyclist football player.
There are some unicycles in the documentary but not the lefty with âUNIPSYCHOâ on the handlebar/frame as in the image.
Iâd guess it is photoshopped image or a nonworking model for a couple reasons, 1. There seems to be no other photos of it and 2. The pedals look to be about 200mm long and would be well in the pedal strike area. Also has a bicycle saddle, weird brake cable/handle and the wheel spoke and left crank arm do not seem to be in line.
Mike Burrows (https://en.wikipedia.org/wiki/Mike_Burrows) has been a long time proponent of the cantilever axle on bikes and trikes.
His use of a cantilever back axle on the âspeedyâ or Windcheetah recumbent trike (two wheels at front, one drive wheel at back) would predate the Cannondale Lefty fork by quite a few years I think. He has also made quite a few bikes, both âstandardâ and recumbent with cantilever/stub axles.
Youâre right with the saddle. That doesnât look like a uni-seat and is quite the give away. The cable that dangles like that I could sort of understand. On my unis, the cable is also quite long so I have to loop it around the frame a few times.
So uhm, there is no one on this forum who has thought of taking the challenge of building a lefty unicycle with a different hub?
Im am not at all technical with hardware and wouldnât know where to start.
Some service:
- we already had this discussion in this thread, you could maybe find some additional information there.
- This thread shows a picture of a ârealâ lefty unicycle (by accident)
- In this thread of the German subforum there were several design concepts made and discussed, how this could be realised. It ends with a picture of a realised unicycle.
btw: Iâm not the omniscent memory, but we have a wonderful and perfect working search function here