Definition of geared uni (Closed for comments)
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Started
There is no definition of geared unicycle. Shall unicycles with gears (2 or more) and transmission be distinguished?
Comment
I don't think thats necessary. In my opinion we have more than enough categories, so geared should just stay geared.
Comment
I think he is referring to the lack of definition for "geared", which is probably something we need. Here's a first stab:
Geared:
Any unicycle that allows the wheel to rotate at a speed different from the speed of the crank arms.
Short & sweet is the best, if it's adequate. The above definition doesn't talk about the mechanics, ratios or even if the uni is geared down. But is it enough of an explanation?
Comment
What about freewheels? Is that a standard unicycle? (I say not really...) Is that a geared unicycle? (No.)
Comment
I understand that geared unicycle is the one with ability to shift a gear up or down. So, when there is only one gear available than it is unicycle with transmission rather than geared.
I would keep all unicycles without ability to shift gear up or down (standard hubs, freewheel hubs, hub with transmission or hunirex) in category ungeared.
Geared unicycle- the unicycle that has ability to change gear.
Simply:
Ungeared unicycle - single speed (with freewheel or not).
Geared unicycle - multiple speed.
Comment
I think hunirex should fall under the geared category, since it allows you to ride faster than a traditional unicycle with the same size wheel. What about the following definition:
An ungeared unicycle is one that has the equivalent gearing of 1:1 and doesn't have the ability to shift gears. Anything else is considered geared.
Comment
I think what we're looking at here is a geared unicycle vs a shiftable geared unicycle. Thus we have:
Ungeared unicycle (1:1 ratio)
>ungeared fixed
>ungeared freewheel
Geared unicycle (non 1:1 ratio)
>shiftable geared (e.g. Schlumpf)
>non-shiftable geared (e.g. Hunirex, non 1:1 giraffe, Christoph Hartmann's internal planetary fixed hub)
There are some additional edge cases, especially since there are some very clever custom unicycle builders including
>quasi-shiftable geared: for example where you have to stop, loosen a chain, swap a cog over, etc. but where the shifting is not on the fly
>freewheel geared: I haven't seen one of these yet, but it would be easy enough to build on a giraffe for example
Unless someone has a problem with the terms I have listed here above, as a unicycle geek and native english speaker, I would like to suggest that we use these terms as we continue in this thread.
Comment
You unicycle geek! I think you have it pretty well covered. In other words, possible overkill for where we are today in Road racing. Good for being prepared for an even geekier future, but are we in a place where we even need to distinguish between shiftable and non-shiftable? I'm trying to picture a type of race where a freewheeling, geared giraffe would be an advantage... :-)
Someday I can see people requesting a separate category for shiftable gears vs. Hunirex and similar unicycles, perhaps. Or to use a Schlumpf in a non-unlimited race, with a promise that they won't change gears. So I guess it doesn't hurt to be prepared!
Comment
My point is only to have a clear definition of geared unicycle, as at the moment it does not exist.
I am not native English speaker and for me geared means shiftable, so I was cnofused while Christoph was clasified in geared category while rideing his hub. Just to clarify things for the future.
Comment
How about this, as a generic definition for "Geared":
"Any unicycle that is capable of of a non 1:1 ratio of wheel speed to pedal speed"
That is intended to cover any version of geared; shiftable or not, and may be sufficient for the near future. The wording could probably be improved, but I try to think in terms of translation to different languages, and avoid leaving things we may not realize we're assuming.
Comment
I am not a native English speaker but I would prefer the term "non-geared" over "ungeared". To me, ungeared implies that there has been a gear but it has been removed. A Schlumpf with the internals welded in 1:1 mode would be ungeared.
Scott in his proposed list of terms missed a 1:1 giraffe under Ungeared, I think.
As to the original question: I like John's definition in his last post. We should complement it by defining any other unicycle as Non-geared.
Note that a 1:1 freewheeling unicycle is Geared under this definition. Not sure if this makes sense. A freewheeling uni can reach higher speeds downhill (mostly theoretically) than is possible with 1:1 pedalling, but so can someone on a Non-geared unicycle when gliding or coasting.
Finally, I totally do not see the need to distinguish shiftable versus non-shiftable (but still geared) unicycles as separate award categories.
Comment
Current definition of unlimited unicycle:
1.D.1
"Unlimited unicycle: Multiple wheels are permitted, but only one may touch the
ground and nothing else. Is human powered only. Gearing and/or a transmission are
allowed."
For the moment there is not definition of gearing or transmission. I though that those words mean different, but looks like there is no difference.
I suggest change the definition to following:
"Unlimited unicycle: Multiple wheels are permitted, but only one may touch the
ground and nothing else. Is human powered only. Gearing (shiftable or not) and/or freewheel are allowed."
and add following definitions:
Gearing - mechanism transferring rotation speed of crank arms to different rotation speed of wheel (Does not include freewheel).
Freewheel - mechanism allowing a rider to stop pedaling while keeping wheel in motion.
Bill,
I do not want to create more (separate) categories, yet.
Comment
Ups, there is no Bill in discussion. I didn't know that Klaas is a first name. I'm sorry, Klaas Bil.
Comment
I'm not a native English speaker but it seems to me that the Rulebook uses "transmission" incorrectly in 1.D.1. In a vehicle, transmission in general is the system that transmits the energy from the engine (in our case the rider's legs) to the wheel(s). The transmission in a car includes the gear box but also axles, one or more differentials, the clutch etc. In a unicycle this is usually simpler but a regular unicycle technically has a transmission (crank arms are part of it). In a standard unicycle the transmission does not include gears.
I think what is meant by "transmission" in 1.D.1 is any system that is not direct drive. E.g. a giraffe with identical top and bottom sprocket. While that is a transmission, we don't need to say that it is allowed, as crank arms are allowed in standard unicycles. In other words: a transmission is always allowed. It would be sufficient to say that gears are allowed. Or even more accurately: a gearing ratio other than 1:1 is allowed.
In short, I like Maksym's proposal. However, I'd like to edit the Freewheel definition a little. There are several ways to stop pedaling while keeping the wheel in motion, such as gliding, coasting, or doing a crank flip. Suggestion: Freewheel - mechanism allowing the wheel to rotate forward while the cranks are stationary. (Maybe we could drop "forward", but on the other hand a regular freewheel works only one way. If the wheel can turn freely in both directions while the cranks are stationary, would it still be called a freewheel?)
@Maksym: you're welcome. Klaas is indeed my first name. But I'm used to seeing Klass, Klaus, and Bill, and I don't take offense.
Comment
...If the wheel can turn freely in both directions while the cranks are stationary, would it still be called a freewheel?...
Above is kind of free wheel (it is easy to make it from Schlumpf hub, if you remove planetary system than you can shift between 1:1 and freewheeling), and it works in both directions.
Of, course Klaas, we can stop pedaling on many ways. What about this definition:
Freewheel - mechanism allowing a rider to stop crank arms while keeping wheel in motion.
Comment
> ...If the wheel can turn freely in both directions while the cranks are
> stationary, would it still be called a freewheel?...
> Above is kind of free wheel (it is easy to make it from Schlumpf hub,
> if you remove planetary system than you can shift between 1:1 and
> freewheeling), and it works in both directions.
Well, if someone mentions a freewheeling unicycle (or freewheeling hub in general), I think of one capable of freewheeling in only one direction, and transmitting power in the other direction.
> Of, course Klaas, we can stop pedaling on many ways. What about this
> definition:
> Freewheel - mechanism allowing a rider to stop crank arms while
> keeping wheel in motion.
That is acceptable to me. I do think, though, that my definition is a bit more precise, and one word less. If we drop "forward" it is even two words less.
Comment
A freewheel that can turn freely in both directions is a really, really free wheel. Like a BC Wheel. But they don't accelerate very well (level ground), or at all going uphill. :-)
The Freewheel definition above sounds short and simple.
@Klaas: "Note that a 1:1 freewheeling unicycle is Geared under this definition."
Do we really have an expectation of Freewheel unicycles in Road races? I can't figure a scenario where one would be useful, except in a race that's primarily downhill, which would be a type of race we don't typically have yet. In this case, I would include Freewheels in the Geared, or Unlimited category since they are not limited by foot speed when going downhill.
Here is an edit of the Unlimited definition, putting the more important details first:
"Unlimited unicycle: Is human powered only. Gearing, shiftable or not, and/or freewheel are allowed. Multiple wheels are permitted, but only one may touch the ground and nothing else."
In the area where definitions would be listed (or in that section if not a separate area):
Freewheel - mechanism allowing the wheel to rotate in one direction while the cranks are stationary.
Gearing - any mechanism that transfers the rotation speed of crank arms to a different rotation speed of wheel
----
For Freewheel I used Klaas' definition, but changed 'forward' to 'in one direction'. I think the reason we specify this is mostly to help people understand what type of system we're talking about when we say Freewheel, and don't mean a completely free-spinning wheel, which would be pretty useless.
For Gearing I slightly modified the wording; people who are better English experts may fix this, but otherwise I think it's a more correct sentence.
Comment
John,
According to recent definitions we worked out freewheel does not mean geared.
While in freewheel, the rotation of cranks is NOT transferred to rotation of a wheel.
Although, there might be mechanism that join gearing and freewheeling, like riding normal bicycle on rear wheel.
Regarding, complete free wheeling. It is not useless if it is possible to shift from freewheeling to fixed. With a bit of practice it might be very profitable to use it in hilly race. So better have new definitions ready for this case.
I suggest to remove "in one direction".
Freewheel - mechanism allowing the wheel to rotate in one direction while the cranks are stationary.
Comment
I like John's definitions.
The only edit I would to is to remove "in one direction" as per Maksym's comment. This edit doesn't hurt and allow for bidirectional freewheel in Unlimited - why not? I have seen video's of someone in slightly hilly terrain who went downhill faster on a freewheeling unicycle than he could have pedalled on a fixed hub.
(By the way, I disagree with a BIT of practice, this should be TONS of practice.)
It still occurs to me that Standard Unicycle (if we still use that term, see discussion 26) includes a few elements that also should apply to Unlimited Unicycle, and vice versa. At least:
- "Is human powered only" should also apply to Standard Unicycle.
- "Is balanced and controlled by the rider only" should also apply to Unlimited Unicycle.
This can be solved by changing both to
- "Is powered, balanced and controlled by the rider only"
I don't understand Maksym's first comment. What exactly do you mean by freewheel does not mean geared? Freewheel can include geared (as in most bikes) but it is not the same. So your comment is correct but what is your point?
Comment
Klaas,
My point is that freewheel collection of unicycles is different that geared collection of unicycles but they overlap.
DEF: Gearing - any mechanism that transfers the rotation speed of crank arms to a different rotation speed of wheel
1. Geared unicycle (non 1:1 ratio)
>shiftable geared (e.g. Schlumpf)
>non-shiftable geared (e.g. Hunirex, non 1:1 giraffe, Christoph Hartmann's internal planetary fixed hub)
DEF: Freewheel - mechanism allowing the wheel to rotate in one direction while the cranks are stationary.
2. Freewheel unicycle - (e.g. Nimbus Drift Trike / Freewheel)
3. Geared freewheel - common part of groups 1 and 2. - (e.g. bicycle ridden on rear wheel)
Comment
I agree with all of that, Maksym (except that a trike is not a unicycle, I think you mean a unicycle with the Nimbus Drift Trike Hub).
Still not sure why you made that point, but since we agree on the facts, we can let it rest.