While riding along today I thinging about ways to go really fast on a unicycle.
Has anyone ever built a giraffe or a traveler with a big wheel? Of course a big
wheel giraffe would be very dangerous, especially if you fell off while going at
a high rate of speed. But, you could use the size of the wheel and gears to make
a really fast unicycle. If someone attempted to do this, say to set a Guiness
world speed record on a unicycle (and this certainly won’t be me), would they be
able to ride either behind (drafting) or along side a vehicle with a small crane
arm and a cable that attached to a safety harness to keep the rider from
becoming linguini (sp?) in the event of a fall?
How fast do you think someone (not me, but maybe someoone crazy - like Brett
Bymaster) could go on a geared big wheel?
John Hooten wrote: >How fast do you think someone (not me, but maybe someoone crazy - like Brett >Bymaster) could go on a geared big wheel?
With the right machine, the right rider and motor pacing, 50+ mph should be
achievable. This is based on the fact that bikes without motor pacing have done
upwards of 60, and with pacing have gone over 100.
If anyone does this, please take lots of pictures (and wear a kevlar skinsuit)!
I saw the blue prints and the photos of a non-giraffe unicycle that was geared.
That was many years ago and most of the details have faded. It was made by an
old engineer who lived in Jindabyne (Snowy Mtns. in New South Wales,
Australia). From memory it was powered by offset cranks that sat below (or
above ?) the wheel centre. These ran small chains that in turn drove the
toothed cog on the hub.
The uni was for a guy who did a long ride across Australia (or something like
that - it was a short conversation, many years ago). The unicyclist in question
was from Europe (I think).
When I am more wealthy I will make my own one from new ideas and the few
fragments that I have.
Wayne van Wijk wvanwijk@gil.com.au
I can picture in my mind a world without war, a world without hate. And I can
picture us attacking that world, because they’d never expect it.
At 12:41 PM 9/18/98 +0000, John Hooten wrote: >How fast do you think someone (not me, but maybe someoone crazy - like Brett >Bymaster) could go on a geared big wheel?
Crazy huh? Not crazy enough to do 50 mph. I met the guy that did 152 mph on a
bike(I think that’s the right speed, but I’m not sure). Talk about a big gear –
WOW! He was definitely crazy. The story I heard was that when he first tried it,
he used schrader (sp?) valves (like car tire valves) and the centrifugal force
was so huge that it pushed the valve control in and emptied his tires. He was
apparently wearing a steel suit with lots of leather and got hurt, but not bad
enough to not try it again. For the 152 mph thing he was behind something like a
funny car with a big thing that blocked the wind. Looking at the shape of it, I
suspect that it did more than break the wind – I’m sure that it actually sucked
him along. Its a cool record, but the real stuff is the flat land guys doing 65
mph on bikes without cars pulling them. Thats awesome! Being an avid road biker,
I know how hard that is. About unicycles, it would be extremely unwise to
attempt such high speeds. The configuration of a unicycle does not allow high
speeds like a bike does. A bike and the biker have a natural aerodynamic
position and are very stable at high speeds. Doing 50 mph down a hill on a bike
is easy. Its hard to wipe out going that fast if your going in a straight line
because there’s so much momentum in the wheel. A unicycle is exactly opposite.
Small variations in the riding surface are amplified by speed, so it becomes
exponentially harder to ride at high speeds. High speed gliding taught me that.
20 or 22 mph is easy and actually fairly safe. But the change from 22 to 25 mph
is huge. Its completely different and completely unsafe. It really scares me to
go that fast, but 22 is no big deal. Expanding that to 50 mph doesn’t sound
feasible. Geared unicycles aren’t much safer, but I suspect that speeds over 25
mph wouldn’t be hard. Big wheels are certainly the safest, but the wheel size is
very limited by the height of the rider. Someone want to build a 50" wheel with
4" cranks?? Sounds fast!!! For a Guinness book record, I’ll break 30 mph gliding
or on a big wheel, but other than that, 25 is my max.
Brett Bymaster The Glide-O-Maniac bymaster@purdue.edu
<a href="http://shay.ecn.purdue.edu/~bymaster">http://shay.ecn.purdue.edu/~bymaster</a> The High Speed Gliding Page:
<a href="http://shay.ecn.purdue.edu/~bymaster/muni/hsg.html">http://shay.ecn.purdue.edu/~bymaster/muni/hsg.html</a>
For a guy who happily will go 25 mph with no feet on the pedals, it’s reassuring
to know you have limits.
>The configuration of a unicycle does not allow high speeds like a bike does. A >bike and the biker have a natural aerodynamic position and are very stable at >high speeds. Doing 50 mph down a hill on a bike is easy.
This is true. As you pedal faster on a unicycle, you become less stable due to
the frantic motion in your legs. This is why we can’t ride up some things bikes
can, like quarter and half pipes, because we always have to pedal wherever we go
(outside the limited range of coasting and gliding, which is mostly done on
level ground).
>Geared unicycles aren’t much safer, but I suspect that speeds over 25 mph >wouldn’t be hard.
Gearing the unicycle slows down the pedaling speed, but amplifies the effects of
hitting bumps, and effectively narrows your balance envelope. In other words,
it’s harder to recover on a geared uni.
>Big wheels are certainly the safest, but the wheel size is very limited by the >height of the rider.
Or you can set up a chain system like some of us saw at NUC, but there’s still a
limit to how big your wheel can be and still be useful.
> Brett Bymaster The Glide-O-Maniac
Cool name, but it isn’t going to stick. You are Bloodman!