Crank lenght restriction (Closed for comments)

Comments about this discussion:


Is it necessary to have crank length restrictions for 20" and 24" wheels while there is no restriction for 700c wheels?


I think its like in motor racing, some categries are focused on best technology combined with best driver and some use identical Material and focus just on the rider. So 24" is focus on the rider and 700c and unlimited more on both. 20" is only usable for 10k and even there it makes not realy sense, just for kids who have the power / will to do it (or parents that want it.


Also I would add that there are two possible approaches to this:

  1. Use the same unicycle and same setup as Track racing (current model)
  2. Allow unlimited crank length because it's a Road race (will confuse some riders, who may show up for Track with wrong size)

I go either way on this, and would rather near from actual riders or coaches who ride 20" and 24" in the 10k. My thought is to keep it same as the track, to continue the comparison of equal unicycles all around. I have been in races up to 9 miles (1993; basically nobody had anything bigger anyway) and it still worked.

Without checking a rulebook, I think 700c didn't have a minimum crank length for Track, but then again it also didn't catch on. IMHO, 24" is no longer a sensible size for racing, for the main reason that bigger wheels are available. I'd like to see us switch to 700c (or equivalent designation) for Track, but realize I've gone off-topic...


Thank you for this question Maksym!

As Olaf said, the standard races is focusing on the rider and not the equipment, therefor i think it's important to have crank seize restrictions.

although i think that 125mm cracks for a 24" wheel is obnoxious, and an old rule that needs to changed. maybe its worth taking a look on the possobility to change the restrictions to 114mm or even 100mm. that might also give us faster races witch makes it more fun for spectators to watch.


If we have a standard category we should also have restrictions for it, otherwise its not standard anymore. I mean every rider has a free choice, so if someone wants to compete with shorter cranks he or she can compete in the unlimited category.

Thinking about the proposal to change the crank length to 114mm or 100mm, just remember that there are also races like one foot or Slalom where 100mm cranks are definitely too short. Then we have a problem, should we then change it for some disciplines and for others not? I don't think that's a good idea to be honest.


The definition of Standard 24"(and 20" for kids) comes from track racing. While I agree that the limitation of 125mm cranks perhaps silly, and maybe 700c racing makes more sense for track, that was tried and never took off. Unless the rules change in the track racing disciplines, I think that the rules are good as is. If you change 24" standard for Road Racing, it would mean that a vast majority racers would need to change their unicycle (or cranks) between the track and 10k discipline and that's unnecessary.


Note that crank length restrictions are only minimums. You can always use longer.

I agree with "lasse_..." (can we get our names to display?) on 125 being too long for 24" cranks, but that goes along with the idea of that being a very outdated wheel size to use. I also agree with Mirjam that if you have a "standard" setup, the idea is for it to be same for everybody. Also that if we're calling it "standard" we have to be careful if there are different versions of it. If we say 24" Standard, it should be the same for any events where it is used.

Responding to Scott (how come your whole name shows up?), yes, if we move to a more "modern" wheel size for Track, people will have to buy new unicycles. If we look at this in the perspective of Unicon attendance, that is a minor expense. I should start a discussion on this in the proper committee....


As a 10k standard racer myself, I think the crank length requirements should stay as they are for road racing (and for track racing, for that matter).

If someone definitely wants to race 10k with shorter cranks on their 24", they can enter the unlimited category. And this is not hypothetical, I know at least a few riders who have done this in an official race.


This is talked about almost every year but we have yet to change it. I guess I have mixed feeling on it. It's nice to keep it as is (forever) so that we can compare times from previous Unicons and really have a standard. Yes technology has changed and gotten faster and better but does that mean we need to change it?

On the other hand, it would be exciting to change it so that new records are broken and we have faster records. But what is the ideal crank size? Some might say 114mm, some 100mm, some might even say 90mm. Guess we don't really know the ideal size unless we opened it up to whatever people want to use and then we would find out what size is fastest. But then it wouldn't be standard anymore as it would be unlimited crank size. Therefore I say we leave it as is.


About crank length:

In Japan, they do some races in an "unlimited crank" category, and we have seen those cranks in some of the Road races at Unicons going back at least to 2002. They can be very fast! I remember not being able to keep up, on my 29er, with a gaggle of little girls on 24" wheels at Unicon 12...

For those that are interested, the reason we use 125mm for 24" racing is (was?) twofold:

  • The main reason: they were easy to obtain, or actually came with the unicycle. At the time, shorter lengths were not easily available.
  • Secondary reason, less important: it's a good all-around size, which works for all sorts of riding (or games) without having to change cranks.

There was a big, excruciating change made, back in the 80s, from 140mm to 125. 140mm is essentially 5.5" and was the most common size on commercially available 24" unicycles at the time. It's what the Schwinns came with. Standard equipment. But later on, more unicycles were being shipped with 125mm cranks, and they were pretty easy to get. The case was made for a change to 125 and it was, eventually, accepted.

So it has happened before. It happened again when we changed crank size for 20", but then it was less noise because it's a smaller subset of riders, who were only represented in the Committees by concerned parents. Some took the issue way more seriously than their young riders did. I never met a kid who cared one way or the other, but to be fair, none of those kids probably paid for their new cranks (or unicycles).  :-)

So we have old racing times from the days of 5.5" cranks. We have more old racing times from the days of racing in yards instead of meters (pre-IUF). We have old racing times from the original (pre-1989) Obstacle/Slalom course. Everybody was, eventually, okay with the changes. After all, you get to reset the clock and start fresh!

Nobody has brought up (yet) whether they think shorter cranks would be bad for acceleration. They would. They would probably be terrible for the Slalom. You would have to bring multiple sets, and change them out. But I think I would stick with 100mm for the 100m. A slower start would presumably be surpassed by a faster top speed. One Foot race? Not sure.


Perhaps this is my interpretation but it seems like Maksym's original post was not about changing the size cranks for 24" wheels but rather the disparity between the fact that Standard 20" and 24" have crank limitations but when 700c is a Standard category in road racing (like in the marathon) it does not have restrictions. We have gotten very far away from that point.


You get my point Patricia, thanks.

After this discussion I understand that limits for cranks were set to keep the same standard as for track racing (Although I am not proficient with track racing rules, yet). 

I realized that those rules are not only for Unicon's 10k or Marathon, but for other smaller road races too. I would probably never ride 24 inch on road race but some kids can do. Having standard crank size is good to maintain similar racing conditions among riders and I think if it is standardized than it shall be the same as on track. 
The problem affect only kids but they don't really care I think. Also, if organizer wants to make spectacular race with high speed than 24" category does not suit it anyway. The standard 700c or unlimited categories are without limits to cranks so it doesn't influence road racing on the highest level. 

Let's keep this rule as it is. Or change parallel with changes to standards in track racing.


I agree with you, Maksym. You can close the discussion if you like, since you were the one to start it you should be able to.

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