# Is that epicyclic hub ratio correct?

On gear ratios that I’ve seen in the past, it’s always followed an
input:output standard. Harper’s Hub ™ has been described as having a
1.5:1 gear reduction. Reduction would be correct, because at that
ratio, it would take 1.5 turns of the pedals to turn the wheel one
revolution. Great for muni. It would be kind of comical if that’s how
it turned out, but I doubt Harper is that careless.
Once people start talking about the effective wheel sizes, the
description then changes to a gear multiplication of 1:1.5, requiring
only 2/3 revolution of the pedals to make one revolution of the wheel.
All gear ratios that I’ve seen, however, have had the 1 on the right
side of the colon, so Harper’s Hub ™ would have a .666:1 ratio.

I really need to sleep, but I can’t. I just bought a new uni.

John

Harper is on the opposite side of the world, and is correct. In fact, the main perpose of the device is to test quantum mechanic theory regarding an epicyclic rider crossing the prime meridian. I for one plan on calling in sick that day, stocking up on canned food, and pulling the hatch closed on the basement.

Christopher

> On gear ratios that I’ve seen in the past, it’s always followed an
> input:output standard. Harper’s Hub ™ has been described as having a
> 1.5:1 gear reduction. Reduction would be correct, because at that
> ratio, it would take 1.5 turns of the pedals to turn the wheel one
> revolution. Great for muni. It would be kind of comical if that’s how
> it turned out, but I doubt Harper is that careless.
> Once people start talking about the effective wheel sizes, the
> description then changes to a gear multiplication of 1:1.5, requiring
> only 2/3 revolution of the pedals to make one revolution of the wheel.
> All gear ratios that I’ve seen, however, have had the 1 on the right
> side of the colon, so Harper’s Hub ™ would have a .666:1 ratio.
>
> I really need to sleep, but I can’t. I just bought a new uni.

I think that whatever the ratio says he’s got it the right way round because
he’s driving the planet cage and taking the output off the outer gear ring,
whilst fixing the sun gear using the tabs attached to the frame. On
http://www.sturmey-archer.com/p20.htm theres a little animation of how this
works to make the outer ring go faster than the cage holding the planet
gears is turning.

Joe

Watch out for those dented cans. Pineapple juice mixes well with orange
juice or Malibu rum.

John

rhysling wrote:

> Harper is on the opposite side of the world, and is correct. In
> fact, the main perpose of the device is to test quantum mechanic
> theory regarding an epicyclic rider crossing the prime meridian. I
> for one plan on calling in sick that day, stocking up on canned food,
> and pulling the hatch closed on the basement.
>
> Christopher
>
> –
> rhysling
> Posted via the Unicyclist Community - http://unicyclist.com/forums

Oh my god!! I just tested the thing and not only is the gear ratio inverted and negative, the hub rotates around the vertical axis while the axle is cranked in the horizontal axis. Well, at least it is frictionless like I intended and as soon as you start turning the axle it accelerates on its own and…oh no…it’s turning TOO FAST…IT BURST INTO FLAMES…AHHHHHHHHHHHHHH.

Yeah…I got it right. Thanks for your concern.

will you be able to use this in the unicycle races at unicon?
just wonderin
dan

ps. harper-that is sooooo cooool (the hub)

pps. i want one

> will you be able to use this in the unicycle races at unicon?

For a second you had me wondering if our rules covered this…

But they do. Regular racing is only allowed on “standard” unicycles, which
are defined elsewhere as having direct drive.

This type of unicycle would, however, be legal for off-road (MUni) events,
and any event listed as “unlimited,” such as the unlimited category of the
marathon. Plus any non-racing events, such as artistic. I’m not sure if it’s
a gray area for hockey and basketball though.

Bring it on!

John Foss
President, Unicycling Society of America
President, International Unicycling Federation
jfoss@unicycling.com
www.unicycling.com

Great, so you can Join the Cokers in the unlimited race

Roger

The UK’s Unicycle Source
http://www.unicycle.uk.com

----- Original Message -----
From: “John Foss” <john_foss@asinet.com>
To: “‘uni-man-dan’” <forum.member@unicyclist.com>; <rsu@unicycling.org>
Sent: Saturday, February 16, 2002 12:44 AM
Subject: RE: Is that epicyclic hub ratio correct?

> > will you be able to use this in the unicycle races at unicon?
>
> For a second you had me wondering if our rules covered this…
>
> But they do. Regular racing is only allowed on “standard” unicycles, which
> are defined elsewhere as having direct drive.
>
> This type of unicycle would, however, be legal for off-road (MUni) events,
> and any event listed as “unlimited,” such as the unlimited category of the
> marathon. Plus any non-racing events, such as artistic. I’m not sure if
it’s
> a gray area for hockey and basketball though.
>
> Bring it on!
>
> John Foss
> President, Unicycling Society of America
> President, International Unicycling Federation

>

> rec.sport.unicycling mailing list -
www.unicycling.org/mailman/listinfo/rsu

Or make a geared Coker, what would people say then?

Re: Is that epicyclic hub ratio correct?

“WAIT FOR ME!”

AccordNSX wrote:

> Or make a geared Coker, what would people say then?
>
> –
> AccordNSX
> Posted via the Unicyclist Community - http://unicyclist.com/forums