Rims!

I’d like to start a new topic. What’s up w/ uni rims?

  1. What’s up w/ uni vendors doing almost nothing to offer light weight tubeless rims?
  2. What substitutes are ppl finding effective from the tubeless MTB offerings (aluminum and carbon alike)?

Why aren’t M4O, Qu-ax, Nimbus doing more to keep up w/ advancing rim tech and functionality? I know there’s the KH tubeless rim but what if you want something that isn’t a mile wide? Nimbus seems to be selling the same rim as well, 55mm outside width, 50mm inside.

AFAIK, 35mm internal width is the sweet spot that can accommodate everything from a 2.25 - 3.25in wide tires. But all we’ve got on the uni side is the Nimbus Dominator 2 at 33i and it’s not tubeless and doesn’t work well tubeless (the stepped bead area is reluctant to seal or stay sealed) and its flywheel heavy at 900+ grams for the 29r.

What are ppl using from the bicycle side? I built a WTB KOM 29 x 32hole and so far so good but I wish it were 36hole. Light Bicycle seems a popular option but how do they ride? Carbon can be brutally stiff. I haven’t found any aluminum tubeless 36 hole rims but for Velocity however they’ve nothing at 35i, only 30i (Blunt) and 39i (Dually).

Going tubeless seems a no-brainer for all the same reasons it’s become the standard for MTB. Why hasn’t the same happened for Uni? Burping hasn’t been an issue w/ the KH rim (it’s REALLY tight) and my WTB KOM has only burped w/ one tire that had a very stiff sidewall. Why hasn’t the (admittedly small) uni industry converted to tubeless as well? Can you even find an old style clincher rim for MTB any more? Yeah, at every unicycle shop but you may need 36hole hubs…

So 2 issues here:

  1. What’s up w/ uni vendors doing almost nothing to offer light weight tubeless rims?
  2. What substitutes are ppl finding effective from the tubeless MTB offerings (aluminum and carbon alike)?

Don’t think there’s really anything up with vendors. From what I have read the costs of making new versions of rims are exorbitant to say the least. And while tubeless is going to be nice, I suspect that there’s little profit to be gained by offering this to the niche unicycle community- over the profit from currently available uni-rims.

I also suspect that 85% of riders probably don’t care and are going to be happy riding the rims and tyres provided stock.

Not least that tubeless isn’t going to be provided as standard in terms of set up - so this would be always a post purchase switch to tubeless even if rim + tyre is compatible.

I am building up a LightBicycle rim and at 36h - but once you get to the cost of building a custom wheel you’re in a different space to what unicycle vendors cater for - and in fact I feel they cater for it pretty well already.

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I think I agree that there hasn’t been sufficient clamor for tubeless rims/wheels to motivate vendors but aren’t the vendors in competition with each other such that they could gain a competitive advantage by offering them? As a uni company it would only benefit you to offer advantages that the competition doesn’t. For those customers who don’t care it makes no difference but some will value the option to easily convert to tubeless. I mean, somehow unicycles went from steel to aluminum frames and from no brakes to rim brakes to disc brakes. I don’t think there were riders clamoring for these changes yet they happened because each company wanted to be current with the best technology. Yet no tubeless for you! (cept KH and Nimbus a little).

The tooling cost is probably mute because there are already scads of companies making tubeless rims for the bicycle market, they just aren’t 36h but 32 and increasingly 28 and 24h! If spoke holes are drilled then making 36h tubeless shouldn’t involve prohibitive equipment investments. AFAIK there are no KH, Nimbus, Qu-ax, or M4O factories but each company contracts out the parts they want manufactured to China and Taiwan. M4O may have some productive capacity cause they sell “made in Italy” stuff, but again it could be a domestic Italian bike manufacturer doing it, but I’m speculating.

There’s something else afoot. Part of it must be that uni riders don’t pinch so hard and often–like mtb riders do–so they aren’t as aggravated by pinch-flats. Still dropping 300grams of tube is something very noticeable in a good way. Even if you add back 100 in sealant and tape.

Maybe Rodger or Kris or Marco or Dieter(?) wish to explain it? There is an explanation, I just don’t know it…

By the by let us know how it goes w/ Light Bicycle. I wonder if their productive capacity is impacted by the latest BA.2 wave?

That might depend on where you live. Personally I don’t deal with thorns or sharp rocks, and don’t run low enough pressure to pinch flat, so I have no desire for tubeless. But I’m far from an extreme rider.

I also have a wheel with a KOM (light) rim. Nice wheel but you’re right, you need to find a 32 hole hub.

I think the 32 hole hub is really the answer to rim availability when it comes to muni. I don’t think we can get away from 36 hole completely though, as it’s more suitable for larger wheels.

I think this is the key. The people on forums like this are the passionate few, not really a broad representation of unicyclists in general.

Maybe if more uni riders came over from MTB and were not afraid of the minor hassles of tubeless? Car and truck tires went tubeless, what, 100 years ago? Even the Onewheel is tubeless! Sorry, rant off.

I prefer 36h for every uni wheel because it’s stiffer laterally and I’m sure, less prone to broken spokes…

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What are basic, buy it in every “normal” (non MTB specific) bike store Mountainbikes equipped with? Tubes. Do the buyers of those care? No. Even the most high-end complete unicycle you can buy is essentially the equivalent of an entry level mountainbike.

Car tires also weigh a lot, are only able to be mounted with specialized machines, have very different requirements to rigidity (size of bump in relation to tire width for example)… apples and oranges.

I’m pretty sure Qu-ax RGB rims work for tubeless (as does KH). And for the rest of the manufacturers:

  • 95% of unicycle riders don’t care.
  • The ones that care, don’t buy complete unicycles, so not really a need to offer a rim for them. The offering on the bike market isn’t massive for 36 h rims, but there are enough ones can find (lightbicycles seems to be the favourite, but I know of a few others who have found suitable aluminium rim)
  • Every unicyclist seems to think they are Ryan Kremsater and therefore need a super strong wheel (to the lightweight point)

I think we will get there if there are reasons to change rim profiles (or extrusions from other manufacturers become available for cheap), but there just isn’t much incentive currently.

I consider myself somewhat tubeless curious, mainly for the ability to run tire inserts, but I’m not sure if I have the spare cash to invest in an experiment right now - and I also have had zero issues with heavy duty casings and tubes on my Muni, so the incentive to switch is pretty low.

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One of the primary reasons for inserts, preventing pinch flats, is moot. You’ll probably never split a sidewall by pinching it which takes considerably greater force than splitting a tube by pinching it. The other reason is for the ride characteristics (mostly courtesy of cush core but also rimpact and tannus tubeless) which you may appreciate. But I suspect most of those characteristics can be had by using the right tire w/ the sidewall construction you prefer.

I tried a Vittoria Air Liner in a maxxis w/ exo sidewall and it just made the tire too bouncy. If I aired it down into the teens (psi) there was way too much squirm. If I put in enough air to get rid of the squirm then I no longer needed the insert because I wasn’t reaching the rim very often. I’ve tried double down casings too but those definitely don’t need inserts in my experience. YMMV

Bikes convert forward velocity to big rim impacts so they can pretty easily split a sidewall in a pinch. We unicyclists only really encounter high pinch forces by dropping large onto sharp rocks or badly misjudging a curb hop. So the question becomes is the enhanced ride worth the 200+ grams of CushCore…? I know there are very skilled riders who answer that w/ a yes but I doubt I’ll ever get to their proficiency level. But I do like light wheels and ditching the tube is very low hanging fruit. Star thistle abounds on the front range as well…

Tubeless rims have a different rim contact area that locks the tire bead in, kind of snaps it in place. I think only that 55mm wide rim that KH and Nimbus sells is explicitly made tubeless. The Qu-ax rgb looks standard issue clincher w/o the square bead area. I’m sure it can be converted ghetto tubeless but then you get half the tube back in the process.

I’m sure that in 5-10 years everyone will have followed in KH’s footsteps. But I hope w/ less than 55mm wide rims.

The reason why I’m whining about it here is that there are few good options in the MTB world for 36h rims. To my knowledge just the ones I mentioned in the OP

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That would be the reason for me, but exactly, strong casings already seem to provide a lot of that. I’d still be very happy to add 200 grams (or much more) for a better ride. I recently switched from a 26" to a noticably lighter 27.5" (but with a 3.0 tire and not the strongest casing). Then I put a Magic Mary 2.6" with super gravity casing on. The weight reduction going to the 27.5" was noticeable, but didn’t actually change much to how it feels. The change to the magic mary absolutely transformed the ride feel, night and day difference.
I don’t expect as much as that from changing to tubeless with an insert, but we only have one piece of suspension and to me it makes a lot more sense to optimize that than weight. And maybe something like a cushcore would make 2.8-3.0 tires feel less spongey, it’s not that I wouldn’t appreciate some extra volume, if I could get it with a more direct feel.

I’m pretty sure I’ve seen more than one QX set up as tubeless, but maybe those were indeed split tube (and one of them I know was Schwalbe Procore, which also would be very different), that’s why I mentioned them.

When I last looked, there were a few more options for useable aluminum 36h MTB rims (if I find the time I’ll dig through and find them again), but they may have been slightly thinner than 35mm, which for my liking of ~2.5" width tires would still be in a good range. (EDIT: RYDE Rival 35 , DT Swiss H552 (30i) are a few ones I have refound quickly )
To be perfectly honest, I find it very hard to believe that a 32h wheelset is very noticably different to a 36h, both in strength (assuming it’s properly built with good spokes) and in lateral stiffness. I’ve ridden both 48h and 36h and I doubt I could tell the difference in a blind test. I have heard of someone who had issues with a 32 hole setup for muni, but he is a bit of a parts breaker anyway.

[quote=“Unitardis, post:1, topic:273359”]

  • What’s up w/ uni vendors doing almost nothing to offer light weight tubeless rims?

So I come at this from 2 points:

  1. If you want a carbon lightweight non-36 rim, carbon and light aluminum rims are sold in most places. I built up my Nimbus Oracle 29" with a 36h 495g aluminium rim off eBay. Most go for 28-32 holes but 32 hubs are being made even the new schlump. Should the brand’s stock them? Maybe but they are in a Really small market and it may be hard to compete on items like this. Most of the rims I’ve purchased from M4O and UDC UK were rated for stuff done in the crazy muni vids and I wouldn’t want anything less than that. If you’re looking for that level of customization you can order the parts to Marco and he’ll built it and ship it to you gladly.

Could they stock it? Yes, but people may not but it. The have limited RND budget at it would be better put towards uni specific parts rather than rims which they could get an off the shelf solution from a bike supplier that puts in the research money for cheaper.

  1. They do have a light rim, I built myself a 24" at Christmas this year and UDC was the only place I could find a cheap 24" rim with 36H in their freestyle rim at 495g or so.

My 2 cents:

  • if you’re looking for lightweight alu 36h rims, you should have a look at Dt Swiss store. They have a bunch of them, at different prices. As @finnspin said, H 552 is one of them but you may find other for different sizes and internal width. I have seen some big drops with one of them - ~2m - and it held well.
  • 32h may be great for non-abusive riders and alu rims to 29". 32h seems to not be a great idea for 36" alu rims - @rogeratunicycledotcom did some tests that weren’t successful. So if you want to go on 32h for a 36" wheel, you have to use a really stiff material: carbon.
  • LightBicycles offers lots of different options. If they are trued by a professional, with the correct spokes, they work really great. If you build it as an amateur, well… I broke mine on my second DH training. However, a friend of mine did some big drops - the same ~2m drop - and it didn’t break.
  • Tubeless for unicycling? I’d say yes. I have had a lot of flats - either thorns or drops on rocks - and tubeless would have avoided that. My friend with its LB carbon rim has gone tubeless and he has not had any flat since then! Sometimes a thorn enters into the tire but the sealant just fixes the hole. So tubeless is fine if you don’t want to bother with flats :stuck_out_tongue:

Otherwise, I mainly agree with @finnspin:

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Hey thanks for the leads! I wasn’t aware of the H552 and I’ve never even heard of RYDE! If you remember any others let me know! I would add Nextie carbon rims to the list as well. They can build 36hole rims 34i!

This is a marketing explanation. I agree with it but I don’t find it a very satisfying explanation. It’s more like a justification ex post facto. A more complete explanation would have to account for why the engineers don’t design a better product. My hypothesis is that they just don’t realize how much better tubeless is so aren’t motivated to overcome the accounting and marketing impulses that maintain the status quo. I assume this also reflects the general apathy among unicyclists toward tubeless tech. It’s an ironic aspect of the unicycle market that it is such a late adopter of what is mostly a better way of doing things. You’d expect unicyclists to aver suffering the status quo. But I suppose, as a crude generalization, that most unicyclists aren’t very interested in MTB and vice versa. Consequently they don’t experience the benefits of tubeless tech and don’t know what they are missing so there’s little motivation to change something that is already good enough in the minds of most of the uni manufacturers and their customers. The disinterest in tubeless results from lack of experience. It’s a kind of blind spot. Yes there are more important things to think about but I like good explanations, even if they cover trivial matters. Engineers want to engineer better solutions so why haven’t they in this instance?–That’s a better formulation of my original question. A critical mass of early adopters will change all of this soon enough I’m sure. Diffusion of Innovations Theory is a template for understanding and explaining this stuff. Sorry for the painstaking analysis if you’re still with me!

I mostly don’t care very much about weight. Except for unicycles :laughing:. I’ve discovered that a much lighter wheel is really more fun to ride all else being close to the same. The wheel is a gyroscope that creates inertia as it spins. Reducing that inertia is very noticeable. But you are trying to optimize weight, strength, tracking, grip, stability, suspension, etc. And removing weight usually diminishes some of the remaining characteristics so there’s a tension in that. But hopping around on a light wheel feels so effortless and it steers better. I didn’t know it would make such a difference in the quality of the ride until I tried it. Now I don’t want to unknow this!

I resisted tubeless on my mountain bikes for years, a couple years ago I bought a bike that was setup tubeless. It’s a 27.5 plus setup, while I enjoy running the lower pressure (it’s a hard tail) I don’t enjoy the maintenance that comes with it. I don’t ride nearly as much as I used to, sometimes my bike sits in my garage untouched for 6 or 8 months, and If I decide to ride I need to plan a couple of days in advance to make sure my tires will hold air. For me having tubes and only having to deal with adding air is a big plus.

I think there could be a large percentage of people in my situation. Dare I say the majority of unicyclists? I mean probably the majority of unicycles sold are ridden for a short while, then end up in a closet collecting dust.

Not sure where I’m going with this, but I thought I’d share a different opinion on tubeless.

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Yeah, I agree that if you are an infrequent user then tubes can be preferable, on a bike or a uni. But companies usually sell tubeless wheels tubed b/c they sit in inventory for too long (just like your bike sits in the garage :slightly_smiling_face:). So there isn’t much of a penalty for selling tubeless to ppl who don’t want it cause they just keep the tubed installation that the bike/uni was sold with. I’m surprised anyone sold a tubeless wheelset already set up tubeless!

I disagree. A tubeless setup (rim + tire) may be really hard to disassemble. Lambda people want tires that easily pop out of the rim so that they could easily change the tube when needed. Having a tubeless setup may then be a penalty for those people.

That’s true! I have to prop a 2x6 against my partially inflated tire and jump up and down on it to break the bead w/ the KH 55mm rim, it’s sooooo tight! But it never burps!

Ultimately there is no such thing as a free lunch… But I thought there wasn’t so much overlap between unicyclists and lazy(?) ppl?

I do not see the problem. Anyone can build their own unicycle with a setup of their choice. Why should a mass-produced unicycle be tubeless? Are they all airtight when they are delivered after months of storage? That doesn’t make any sense to me.

With no disrespect to any of the people in the unicycle industry intended, there is very little actual engineering going on. There is maybe a total of 25 people (and that is probably an overestimation) that live of selling unicycles and unicycle parts full time. If the entire “unicycle industry” sums up all their engineering time for a year, it’s maybe the equivalent to 2 engineers working full-time for that year (probably less).

I agree that there is little penalty to making rims tubeless ready for those who care, but you cannot just disregard the money. For the most part, munis are really not the big money maker anyway (those would be simple beginner unicycles).

I’ll do the math one day, but I’m very certain that gyroscopic effects are pretty miniscule on a unicycle and also the importance of weight at the wheel for inertia (in forward acceleration) is vastly overestimated.

  • Unicycles are slow
  • the wheel spins slow
  • the rider is very heavy when compared to the wheel
  • friction of tires on the ground are high
  • For balance reasons you can’t twist/steer the wheel very much when going fast

All that doesn’t add up to gyroscopic effects ever being anywhere near dominant in my mind (and my experience from riding many different unicycles).

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I think weight of the wheel does have a pretty big effect. If you are riding a technical section at a slow pace or climbing you are accelerating/decelerating your wheel everytime you pedal, it’s not like on a bike where you keep a steady pace, the unicycles speed is very up and down. If you take a pound or half a pound off the wheel it most definitely makes a difference after hundreds or even thousands of pedal strokes.

Now a hundred grams, probably won’t make a difference.

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That’s the equivalent of taking a pound off anywhere else, assuming that pound is located at the rolling radius of the wheel (which is the worst case). Or the equivalent of going to pee once, your water bottle being full or empty, and I rarely hear: Oh, riding feels so much better now that my water bottle is empty.
Wheel weight counts twice in linear acceleration, but realistic improvements in wheel weight are pretty small.
Short sketch of the reasoning behind wheel weight counting twice:

  • We know how fast the outside of the tire is moving, it moves exactly as fast as the speed your riding (as long as you are not doing powerslides)
  • so we can calculate the total kinetic energy, which is: E_kin=0.5*m_wheel*v^2+0.5*m_total*v^2 with: m_total= m_wheel+m_other

So yes, wheel weight has a bigger effect, but I think it is often overestimated. They drill into you not to underestimate the effects of rotating mass in engineering classes, but that’s really for machines that spin much faster…

Just picking up a unicycle and twisting (as if I’m steering) it with the wheel spinning vs. the wheel not spinning and feeling the resistance, I’m pretty sure the math for the impact of gyroscopic effects will be similar (but slightly more difficult).

Well, I guess you can throw a bunch of physics at me to prove your case, but I took a pound off my wheel by switching to a much lighter tire, I can attest it made a huge difference in actual riding (not from making my uni a pound lighter, but having that weight removed from my rotating mass). I’m in no way saying you are wrong, I’m sure you know what your talking about. I think we may not be talking about the same thing.

I enjoy conversing with everyone here, many of which are smarter than me. It’s interesting to see how others think and how different it is from me. :beers: