cranks = gears = lateral thinking

“Wayne van Wijk” <wvanwijk@gil.com.au> writes:

> After discussing the problem of gearing a uni we came up with the idea of
> adjustable cranks.

I brought that up on this list/newsgroup in September 1996, and came up with
some rather lame ideas about how it might work. Other people had some better
ideas though, so it might be worth reading the old thread, which can be fetched
from Dejanews.

The URL for the thread is huge, but you can get to it from this one:

http://x3.dejanews.com/getdoc.xp?AN=183907617&CONTEXT=899801332.1685717155-
&hitnum=17

Ken Fuchs gets the DaVincii award for Best ASCII Drawing and Least Silly Design.
His note is at:

http://x3.dejanews.com/getdoc.xp?AN=184355136&search=thread&threaded=1&CONTEXT-
=899801803.1594491482&HIT_CONTEXT=899801332.1685717155&HIT_NUM=17&hitnum=7

Ken made a point about seat height too (that when you lengthen the cranks
you’ll need to lower the seat), but I’d really like to see just how true that
is in practice.

If you set the seat height so you’re comfortable with the cranks fully extended
(or as fully as you think you might extend them during your ride), then the
only problem is that when you shorten the cranks, your seat is at a sub-optimal
height. But you can still reach everything, and even though your legs don’t go
down as far as you’d like, they also don’t come up as far as they did with the
cranks extended. It seems like it’d be less awkward than riding with long
cranks usually
is.

(Why didn’t I think of that 22 months ago when Ken made the comment in the
first place?)

In addition to the ideas mentioned, Jack Halpern wrote:

JH> I have quite a big file with all crank length discusions form the past.
JH> Anyone interested just shouot.

> Anybody out there interested in something like this for their Muni or Tourer?

I’d love to have this. Let me know when you’re ready to ship.

How do you change the gears on a unicycle?

Two ways that I know of
#1 By changing the wheel size 2 By changing the crank length.

Both of these take time and tools.

On a recent journey around outback Queensland I chatted with a guy who in
tandem-cycling around the world. After discussing the problem of gearing a uni
we came up with the idea of adjustable cranks.

I have a rough design worked out and will be seeing the engineers soon.

Anybody out there interested in something like this for their Muni or Tourer?

I will probably need some help from people who understand the amount of stresses
that a crank must take.

Wayne van Wijk wvanwijk@gil.com.au

RE: cranks = gears = lateral thinking

Wayne wrote:

>Anybody out there interested in something like this for their Muni or Tourer?

I don’t mean to rain on anyone’s parade and certainly would not want to stop the
designers from designing. But we MUni riders, at least, are still bending normal
cranks. To be useful off road, an adjustable crank would have to be at least as
strong as what we currently ride.

I wouldn’t worry about trying to make it adjustable on-the-fly either, not until
after the basic design has proven itself to hold up to unicycling.

I’ve seen pictures of adjustable cranks in old pictures. Maybe even on one of
the unicycle Walter Nilsson rode across the U.S. in 1933. Instead of a threaded
pedal hole, it’s a long slot. Somehow the pedal is bolted on with something on
the other side of the crank to hold it in place. That design might hold more

promise than something that telescopes, which would require an awful lot of
metal to be strong.

jf

Re: cranks = gears = lateral thinking

On Tue, 7 Jul 1998, Wayne van Wijk wrote:

> How do you change the gears on a unicycle?

> After discussing the problem of gearing a uni we came up with the idea of
> adjustable cranks.
>
> I have a rough design worked out and will be seeing the engineers soon.
>

Remember that if you change the length of your cranks, you’ll need (want) to
change the height of you seat.

Re: cranks = gears = lateral thinking

Foss, JohnX wrote:
>
> I’ve seen pictures of adjustable cranks in old pictures. Maybe even on one of
> the unicycle Walter Nilsson rode across the U.S. in 1933. Instead of a
> threaded pedal hole, it’s a long slot. Somehow the pedal is bolted on with
> something on the other side of the crank to hold it in place. That design
> might hold more
>

Cranks with this or similar design are on some czech replicas of ordinaries
(Simovcak I think). Manfred Cizek of Vienna, Austria, who just finished a
round-the-world-tour on such a czech ordinary-replica, told me that he always
had to carry spare cranks with him or getting the cranks welded, because they
are likely to break every some thousand miles. He is going a very constant speed
(about 15 mph, 100 miles a day), so stress should not be the problem, rather the
design itself. Btw. we are using unicyle-cranks on our 52’’ WUK-ordinaries.

Georg

PS. looking forward to unicon ix - hope to see/buy some new unis there!

Re: cranks = gears = lateral thinking

Steve Dressler wrote:
>
> >Cranks with this or similar design are on some czech replicas of ordinaries
> >(Simovcak I think). Manfred Cizek of Vienna, Austria,
>
> Hi Georg,
>
> Could you please explain what is an “Ordinary?”

Other terms are Pennyfarthing or Highwheeler (?). They are quite popular in
Vienna, Autria at the moment, since in winter we built five of them and are
riding them all the time (unicyle or ultimate and juggling-clubs on the back!)

> Sounds cool.

Is very cool!

>
> Look forward to see you and your 52’ model at UNICON.

Sorry, it is not a unicycle therefore not at unicon. But, why not visit
Vienna, Austria?

>

Georg

Re: cranks = gears = lateral thinking

>
> Remember that if you change the length of your cranks, you’ll need (want) to
> change the height of you seat.

not really. depends on the crank delta but i don’t change my seat height
for 180 -170.