Why has this never bin made - or have I missed it ? It should have a low drag… and super looks 
remember that I saw the “black hole” by lew (I think) - but only very few was made…
Cannondale has had their “lefty” mountain bike fork for years it only has one leg.
Yes - I know the CD Lefty fork - I was talking road / tri - making a road fork with one leg would be very easy compared to the Lefty… so why not ?
there have been some. most notably the boardman bike. i recall scot nicol from ibis once noting that they are not so exotic as they seem, seeing as every car possesses a one-side supported wheel . . . . . . . four of them, that is.
my cool hawk gt honda has one on the rear, as do ducati 916’s and their decendants.
it is always gonna be heavier than a two-sider of equal strength, and prolly more expensive to make. only real benefit is it looks cool, so i guess that is that.
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Why? Is there any advantage? It is probably less aero and creates mechanical problems where none exist.
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Are you going to use disk brakes on this fork? If not, have to cantilever a brake mounting point out from the fork, or dangle something down from the head tube.
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I don’t know if this fork could be UCI legal.
Ray
They have been used. The main advantage is aero. One properly designed fork leg is going to be more aero than two. Heavier, yes. Check out the current issue of Cycling Pus (I think) its the British bike mag commonly available @ Borders. They have an article about Burrows who has designed some of the most aero bikes ever used.
Here’s why:
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it (and the special hub/hub axle) would be heavier, as it would be not as structurally efficient, so more material would have to be used to compensate for this
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it would generate MORE drag–the frontal area of a 1-sided fork plus the larger hub would, due to structual necessity and the extra material (see above), would be greater than a standard, 2-sided fork
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The #1 answer to your question is the UCI. One-legged forks are illegal, period. The original prototype for the Trek TT bike had a one legged fork, and the UCI nixed it. A properly designed one-legged fork is more aero than 2 legged (an exception would be if you used a fairing, but that is also illegal), despite what you may be hearing from others on the board; this is pretty obvious, really - frontal area is cut in half, fork wise = more aero, end of discussion. Assuming, of course, you maintain NACA or similar profile, which is not that difficult to do.
And then, of course, you would need special wheels…
MH
Hhmm - maybe
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max 50gr for the hub - you could “cut” the material away between the missing leg and the spokes on the hub (reducing frontal area) - while you at it you could make the front hub width only 70-80mm instead of 100mm (reducing frontal area - increasing structurally efficient)
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1 large leg would generated less drag than 2 small - most of the structual necessity could be build in “behind” the leg - almost no increase in frontal area…
You could actually save some time in a flat - just leave the wheel on… you wouldn’t need a QR = less drag / weight
Try http://www.analyticcycling.com/DiffEqWindCourse_Page.html
decreasing Drag Coefficient by 0.01 gives you 1.44min on an IM !
Sorry fredly - didn’t see your reply - but yes - UCI will not aproved it - But no problem in Tri…
But glad to hear that Trek have bin there 
“frontal area is cut in half”
You can’t simply cut off one fork blade. To do a single leg requires that you make the single leg much thicker than a regular fork blade. So it probably would not be half the drag of a regular fork.
As for what is most aerodynamic, beats me. I wouldn’t trust anything but wind tunnel numbers. Regardless of how much faster I’d be, I’d be too scared to actually use one.
I remember reading an article about the original Lotus bike that Boardman used in '92, which had the single bladed fork. Apparently the later, more normal Lotus fork was lower drag than the single, due to lower frontal area and a longer width / depth ratio.
"Post:
“frontal area is cut in half”
You can’t simply cut off one fork blade. To do a single leg requires that you make the single leg much thicker than a regular fork blade."
Total, utter nonsense. You can’t even begin to back this statement up.
Just to begin with, fork blades are, in general, much thicker than they have to be, sacrificing aero for weight savings, and to meet UCI regs. Take a look at an old ashtabula or Hooker fork sometime - steel, heavy as hell, and half the frontal (blade) area of the carbon stuff everyone uses these days (and they test VERY aero.)
Nobody is saying a single leg fork would be LIGHTER - it probably wouldn’t be - but given >= mass to work with, there is no reason you couldn’t design a single leg fork with equivalent (or smaller) frontal area to half of a traditional fork. WORST case scenario, you could redistribute structure in the fore/aft plane (which, by the way, would likely help aerodynamics…)
Note that I’m not making any claims to wheel turbulence/airstream interference/boundary layer stuff (which opens up a whole other can of worms,) just frontal area/simple aerodynamics. A single leg fork would either (potentially) be much better or much worse in regard to these (wheel interference) factors.
MH
I was thinking of designing a unicycle designed for the aero position. Without any front wheel or fork it would have to be faster.
I disagree. And I don’t understand this: (please explain) “you could “cut” the material away between the missing leg and the spokes on the hub…”
Sure, you could make the the front hub width only 70-80mm instead of 100mm–but then why not do that now with a conventional fork? We gotta compare apples to apples here, not apples to oranges.
Sure, you could put most of the structual necessity for the one leg fork “behind” the leg–but again then why not do that now with a conventional fork? If you used the same approach with a conventional fork, you could probably get the blades almost as thin as a knife. The one leg fork would have to be a LOT stronger due to complex shear and bending forces that a 2 legged fork doesn’t experience (it has mostly compression forces). I am not an engineer here, so I hope I am using the right terms…
The unicycle would be great for accomplished Bishop Polishers. Two-handed access is great for servicing the Bishop and his two pawns.
Your screen name is exceedingly funny, but has it been copyrighted by Mr. Tibbs?
Okay, I change it now.
The weight weenines and the people who like standard parts would ultimately make a uniblade fork unfeasible.
One needs to add weight to both the fork AND the hub. This would require proprietary parts. I think I speak for many, and it would be safe to say that tri geeks and roadies both agree on one thing: we like our race wheels, and we don’t want to have to get rid of ANY of them.
Would a uniblade fork look cool? Hell yes. But, between the people who like to race and train on separate wheels and the ones who like light weight bikes, this would languish in the marketplace and some half-price wheel/fork combos that would be still at $1500 a pop would get dusty in the few bike shops that would risk carrying them. Feel free to work on this yourself.
Also, the UCI would put the kibbosh on this ASAP.
I have to agree with bunnyman on this on, the price would be crazy.
The top end C–dale lefty goes for well over $1000, you can get the the new Fox SPV for half the price and it may be a better fork. Would people pay 2.5x for the fork, not to mention the special hubs/wheels, for this? Plus you would be locked into a proprietary setup, one of the reasons I don’t want a Cdale mtb.
A