Racing unicycles

Unicycles and Equipment
1

Can someone help clarify the equipment for different race categories/records for me please?

The IUF records page list shows that the marathon standard record was set on a 29" with 75mm cranks. I thought standard was a 24" (or 618mm) with 125mm cranks?

In races are there different categories depending on the uni used? Does standard just mean ungeared rather than relating to wheel or crank sizes?

Then again the same record page doesn’t show sizes for track records, are they all set on 24"/125mm?

I am considering attending unicon next year and wondering what I should aim for in terms of speed on a given unicycle so as to not embarrass myself being left way behind :rofl:

2

Everything should be in the official rulebook:

It doesn’t seem to appear directly on the IUF website. Quite strange!

Anyway, here are the answer to your questions:

Standard is a confusing term. Depending on the competition, it doesn’t mean the same thing. It is better to talk about classes - e.g. 24 class or 29 class.

For Unicon, if a 10 km race is organized, it must have two categories: 24 Class (including
20 Class for riders under 11 years old) and Unlimited Class. For conventions other than
Unicon, this is recommended.
For Unicon, if a 42.195 km race and/or a 100 km race is organized, it must have two
categories: 29 Class and Unlimited Class. For other conventions than Unicon, this is
recommended.
Using 24 Class and smaller wheels is not allowed in races longer than 20km without
express permission of the racing director. The following chart defines the unicycle size
limitations.

Unicycle Class Diameter Range Min Crank Length Transmission
16 Class 0 to 418mm 89mm regular
20 Class more than 418mm to 518mm 100mm regular
24 Class more than 518mm to 618mm 125mm regular
29 Class more than 618mm to 778mm No limit regular
Unlimited Class No limit No limit unlimited

Track races should be raced on unicycles in the 20 or the 24 class. Please note these unis should be ungeared and fixed - i.e., a freewheel is always in the Unlimited class.

3

Thanks, I’m glad it wasn’t just me missing the rulebook on the website!

It also explains why it’s just the marathon standard record that says it was set on a 29!

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4

It’s here: https://unicycling.org/publications/

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5

Seems I just didn’t look hard enough :joy: thanks!

6

In terms of the actual unicycle, if I were thinking of racing the 24" class. Is there much difference between a 24x2 compared to, for example, the mad4one uni with the 26x1 tyre? I’ve never ridden a tyre that narrow!

There are other differences of course, the m4o uses a narrower hub for instance. Does it feel much different to ride?

7

Oh boy don’t ask such questions, a racer 24" is not one I have yet and I just bought a 24" muni. I have no more space for all those unicycles.

Though when looking at this race for instance, it doesn’t matter so much what tire you have:

The fatter tire won in this case. It just depends on how trained and in control the rider is in order to win. I have the 24x2 tire on my road 24" uni. It is already quite a difference in friction compared to the municycles. I could imagine that a 26x1 has even less friction.

8

That’s pretty much what I thought, as with most things unicycle. The rider matters more than the equipment! But I’m curious. I also kinda think the narrow tyre might be more twitchy and less stable, making it harder to control but faster and more reactive if you have the skill to keep it under control. I’ve ordered a nice slick 2" tyre for my oracle 24 though, so I’ll see how that feels first!

9

If you are going to compete in track events, you have to race in the 24" class.
You may choose between the 24" class and Unlimited class for the 10k race only.

Yes, the difference is significant. Let’s break it down:

Actual Wheel Size

A typical 24x2" wheel has a diameter of 600–605 mm. The Mad4One (and similar track unicycles) 26x1" wheel has a diameter of almost exactly 618 mm. That translates to about a 5–6 cm (2"+) difference in distance per wheel revolution.

For perspective:
In an IUF Slalom race, a skilled rider on a Nimbus 24" rim with a Kenda 1.95" tire takes 44 wheel revolutions. The same rider on a Mad4One Race ISIS 26" (24" IUF) with a Schwalbe RightRun 26x1" tire takes only 42 revolutions. IUF Slalom is about 80m long.
These are not theoretical calculations — I actually counted them.

Switching from a 24x2 to a 26x1 gave my athlete an average improvement of 1 second.
Did it help him win an Expert Unicon medal? No, but it got him into the top 20.

You can do the math to estimate the difference in wheel revolutions over an 800m race or even a 10k event.

Tire Width

Narrow tires are more difficult to control — especially when staying within a lane.
We often debate whether to use a 24x2 or a 26x1 for more technical races, such as the one-footed event.

Narrow Hub and Slim Cranks

There are mechanical advantages to having a small Q-factor on the track.
Mad4One is pretty picky about this, and you should go with them if you want to get that advantage.

That said, the narrow hub doesn’t make as much of a difference as the 618 mm vs. 600 mm wheel diameter — and you need the skill to really benefit from it.

Should you buy a 26x1?

I don’t know. If you’re competing for a medal, you probably should.
But keep in mind: you might need to bring both your 24x2 and 26x1 to Unicon.
Do you have that option?

My Mad4One Race only gets assembled for 1–2 months each year, shortly before competitions. I do travel with two 24" class unicycles, and no larger-size wheels, thus limiting road distance options.

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This is not a Unicon race. AJ, the winner of this race, would not have made it to the top 20 in Bemidji last year. Moreover, 17 female riders finished with better times there. At lower levels of competition, factors like wheel size, hub width, and other optimizations don’t have as much impact. They only start to make a real difference at the highest levels of racing.

OP talked about Unicon, as far as I understand.

11

Yes, they are. Not sure about WW, though, but it doesn’t really matter.

What distance are you targeting?
Here are the top 20 male qualification 100m rides from Bemidji:

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image755×611 55.9 KB

And here are the 100m finals:

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image654×241 18.6 KB

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