24hr race setup questions

My main unicycling ambition at the moment is to compete in the Mountain Mayhem 24 hour race next June, however as all I have at the moment is a 24” muni, I’m going to need a bigger wheel! With Christmas coming up I’ve got the opportunity to ask for money towards a new uni suitable for racing on, but before I order anything I was wondering what other riders use.

At the moment I think that a combination of Nimbus 2 29” frame, KH rim, standard seatpost and KH Freeride saddle would be good, and not too expensive. The hub I’m not so sure about, does anyone use splined or is square taper more common?

Any advice would be much appreciated!

I’d really like to do this race next year too, trouble is i just forked out for a nimbus 36 so it’s a choice between that and the KH 24 to race on. I saw the end of the race this year. Seems most people were on 29 or 36 unis, but im really not sure if i could make it on a 36, the course is nasty.

I actually have been waiting for ages for the Nimbus 36" to come out too, with the intention of getting one with an Airfoil rim and using it for muni racing and road rides. However I’m now thinking about a 29er instead because a I’ve realised how much the 36" is going to be too much money, and the 29er is probably going to be better for muni anyway.

I still want a 36" too, I’ve ridden one twice and they’re great, but I’ll just have to wait a bit longer.

I use a KH splined cranksed and KH rim on my 29er.
It’s good having strong components because then you know your uni can handle whatever you throw at it.
The other good thing about having a splined crankset like is that they do not come loose anywhere near as easily as cotterless cranks do, which is a good thing if your racing because you dont want to be stopping after every little drop or intense downhill to tighten up your cranks (some aluminium cotterless cranks can be very anoying this way).

If yo do decide to get splined cranks, choose a crankset which has a lot of different options for cranklegnth, like the kH onza (127, 140, 150, 165).

The right uni really depends on the course. For the 24 Hours of Adrenaline race in Laguna Seca, everyone was on Coker or 29ers with square tapers; that course was mostly non-technical, with no drops unless you decided to ride the one set of stairs. A 24" MUni might be right for a technical course with drops.

I use my Nimbus 26x3" muni for xc racing - it’s almost the same diameter as a 29er and I reckon the big tyre helps with stability, particularly when tired. I was looked upon as an amateur in the SITS for using a muni (it was even suggested by Des that people shouldn’t be allowed to enter on anything smaller than a 29er), but I got respectable times - I reckon I’d have been no quicker on a 29er.
I’ve recently bought a coker (actually mostly Qu-Ax) with the intension of using it for xc racing, but I can see it being a very long time before I’ve got the guts to ride it on anything steep, and even longer before I’m convinced it’ll be quicker on singletrack than the 26. On a very flat easy course, it certainly quicker (or at least as quick without such a manic cadence). At the moment I’m sure I’d be faster on the SITS course on my 26 than on the coker.
Given the choice between a 24 and a coker, it wouldn’t be such an easy decision - the 24 would obviously be slower on top speed, but you’d have no trouble riding the whole course. If you keep up a steady speed you’ll get a respectable time. If the course is flatter and less technical (or if you’re a really good coker rider) you’d probably get a faster time on a coker.
A 29 (or 26x3, but most people would disagree with me there) is certainly the best all-rounder.


Last year’s KH 29er is pretty cheap on UDC at the moment

If you were to get a coker, and to ride it regularly from Christmas till the race, you’d probably be able to ride okay, cos you’re an alright muni rider already. I think a coker with an airfoil rim, would be a good thing for mountain mayhem. If you don’t get the posh frame and the posh handle, you can piece together a coker from parts for a not insane amount of money, now they have the £20 coker frame on unicycle.co.uk. The airfoil rim would probably be worth it for the big uphills, and because it’s hard to upgrade. You can always upgrade to the nimbus frame and handle without any hassle later.

There was a mix of 29ers and cokers this year. The only person who really had problems riding his coker was Loosemoose, but he’d only just bought it, it was a heavy schlumpf coker, and he doesn’t have much general muni experience either. I did it on the schlumpf, which was okay, but not as nice as a normal 29er, and not as nice as cokering would have been. If I was doing it in 2007, I’d be planning to ride coker.

Having said that, it was a pretty steep course in parts, you’d need to do a lot of practice on the coker to be okay, and some kind of brake might be nice.


Standard Nimbus 29er (like mine) would have no problems at all.
The only problem I had at SSMM two years ago was the rider.

Brakes are only possible if it is not muddy so I would not reply on them. You need to be prepared to ride without them fitted if there is any mud on the course. I tend to do SSMM without brakes.


I’ve done the last three SSMMs on exactly the same 29er; 150mm square-taper cranks and a rather narrow 29er rim from before KH rims were available. I think a 29er is a great choice for a fairly hilly circuit like Eastnor; it might not be quite as fast as a coker on the flat but it’s much easier to ride when you’re tired, it’s dark and you just want to be in bed instead of racing… :slight_smile:

I wouldn’t bother with splined hubs on a 29er - they weigh more and you don’t need the strength if you’re just racing or doing normal cross-country. There is also a much better range of crank lengths available; I change cranks on mine all the time, from 150mm for proper muni to 110s for screaming along flat, smooth tracks or roads.


Well, apart from changing the tyre on my 29er to a Kenda Claw, and slightly longer cranks, I’m hoping to do it this year on a pretty much stock machine.

a 29er would probably see you right for most 24hr races in most conditions. With more practice I would have been more adept on my schlumpf coker, but as joe said its weight and my lack of experience meant that I got faster times on my 26x3.

I’d also like to state its not my lack of muni experience in general that was the problem (I was the top placed brit in the extreme DH at unicon after all :p), but more my lack of confidence and inexperience with both my equipment and 24hr racing. I went into SSMM knowing nothing, and learnt a lot. Next year I will be much more prepared, and will probably do my first lap on either a borrowed 29er or my 26x3.

Nothing quite prepares you for racing narrow singletrack with bikes except for doing it.


It’s heavier, and has a slight crank play. Both are more noticeable when you’re completely knackered and riding the wrong way over rutted grass.


Maybe not, but vast amounts of riding (if possible on similar terrain, with similar equipment) would help.

As a biker and unicyclist I think unicycling in general needs to be a bit careful about 24hr races. There are plenty of bikers that would prefer to see unicycles banned from these races. Generally the unicyclists do well enough to justify themselves, due to a combination of reliability in bad weather and silly fast riders. The speed difference between the two can be quite a lot, and if it’s combined with unicyclists falling off lots or walking more than riding then a lot more people will start to wonder if maybe it would be better with just bikes.

And on that happy note, I’ll just add that 24hr races are excellent fun, and I’d recommend racing in one. To that end, go and ride lots.


P.S. 29er would probably be best, coker if it’s dry and you ride it a lot.

Cheers everyone, lots more for me to think about! Seems like a 29er is still the most popular choice, I think I’m pretty much convinced that this is what I’ll go for.

I’d still prefer a 36, but reading what everyone says about how bad they are in mud is putting me off. If I get a 36 it’s highly unlikely that I’ll have anything else to ride if it’s muddy (apart from my 24"), and I don’t fancy taking my chances with the weather! A 36 is also going to be lots more money, even if I get the cheap frame, because of the Airfoil and tyre being so expensive.

Has anyone else had any problems with alloy square taper cranks coming loose, like willdabasssist said?

Here are the things I’ve learnt about 24hr offroad uni racing, from the 4 or so races I done…

Its nice to have both a coker and a 29er if possible! During the day cokers with 170mm cranks can be the uni of choice; while at night 29ers are generally better. This has been the pattern for most 24hr races I’ve done - cokers in the daylight and 29ers for night laps. However this year’s Moonride was very wet and muddy and I only did one lap on my coker - all the others were on my 29er.

In the races I’ve done where it hasn’t been wet n muddy I’ve done some experiments comparing lap times on the coker vs 29er. My coker laps have been generally faster by a few minutes, but my 29er laps seem less energy draining, probably because it takes less energy to keep a 29" wheel rolling and less to accelerate and deccelerate.

I would avoid the Nimbus II 29" frame if possible and get a Nimbus (unicrown) frame. My friend had a Nimbus II 29er for a while and found that it was very wide at the top - at the perfect height for whacking his inner knees. I rode his uni for only a few kilometers and whacked myself painfully numerous times. Within a few weeks my friend had replaced his frame. Honestly get a standard Nimbus 29" frame, not a 29" nimbus II!

I have had problems with square taper cranks coming loose in 24hr races. You definitely want to go splined if you can afford it. That way you know your equipment isn’t going to fail on you in the middle of a very dark night lap, resulting in a long walk back to base.

A $-saving option to consider is to put shorter cranks on your 24" muni. I’ve found that most 24hr race courses are designed to be ridden by relatively inexperienced MTBers and are therefore not very technical. This makes using long cranks on your muni rather pointless. A 24" muni with 150mm cranks is fast and 140mm even faster!

I’ve never had any crank come loose on a unicycle, alunimium or steel. I always carry a crank spanner because of all the tales of loose cranks, but mine have never even needed tightening. I’ve had a pair of ProWheel alloy 150s on my muni for more than a year with no problems - I removed them a couple of weeks ago to change the bearings and that’s the first time a spanner has been near them since I fitted them. In that time I’ve done the SITS, Snowdon, a few short xc races and hundreds of miles on rocky Dartmoor trails. No big drops though (nothing more than a foot or so) and I’m much more of a roller than a hopper. I just fit the cranks, do them up tight (40lbf or so) and they’re fine. Perhaps it’s my riding style, or perhaps I’m just lucky. Saying that, I’ve only once been on a ride where somebody had a crank come loose - and that was already bent from doing 5’ drops before we started.


That’s disappointing about the Nimbus 2 frame problems, I really wanted one of those if I go for a 29er. I reckon they look much nicer than the unicrown frame, and also they would hopefully have enough clearance for a WTB Weirwolf tyre if/when they ever become available in the UK. Thanks Tony for pointing it out though, it’s definitely something that will influence what frame I choose.

As for short cranks on a 24, I’ve already got 125s on mine! It’s pretty quick but I reckon a 29er would probably still be faster. Steep rough climbs aren’t too easy on it either, although maybe this would be the same on any uni with cranks the same size relative to the wheel.

If I can afford it I think I might go with the KH Moment hub instead of square taper. It’s only about £30 more with cranks, and I could also use Qu-Ax ISIS freestyle cranks if I wanted it to be faster for road riding.

Somehow I think I’m more confused about what to buy now than before I started the thread:p

My 29er has a Nimbus 2 frame, and whilst I’ll admit that I’ve not done much off-road stuff on it, I’ve covered a fair few hundred tarmac miles and I’ve never had a probmelm with the frame hitting my knees.

It also fits the 2.35 Big Apple and the 1.95 Kenda Klaw tyre with no prolems either.

Dunno if that helps your decission :slight_smile: