Quick question about seat tube length

Yes, a neighbor of mine was killed 17 years ago on American Airlines Flight 587, which went down after the rudder fell off. Metal fatigue was partly blamed, I think. Metal fatigue was also mentioned in the case of that Southwest Airlines flight a few weeks ago where a passenger was killed by being sucked halfway out of the plane after fragments of one of its turbines knocked out the window next to her. Airport security keeps getting more invasive, but maintenance of aging fleets of aircraft keeps getting outsourced, cut back and downsized. Many US airlines now have their maintenance done in the US South, where the mechanics have no unions, or even in Central America.

Even if you end up doing a lot of unicycling (which most unicycle buyers do not), it will probably be months or maybe even years before you are attempting stuff that would destroy a Nimbus II (unless you are very heavy).

I never had a Nimbus II, though. I went from a $30 unicycle (which I had to replace many parts of in order to free mount or ride more than a short distance without extreme discomfort or even occasional bleeding) to an Impact-Nimbus-KH hybrid almost-trials unicycle.

So basically all the supposedly high-end unis have issues. The KH20 snaps, the IG has cheese bearings, pick your poison. What’s the word on the trials Nimbus Equinox though? The frame looks skinny and flimsy but is it? I’m beginning to get the feeling all unicycles are made of cheese.

That’s worrying…

I’m probably underestimating the time it takes to get to even level 1.

The one I bought (and returned) a couple of weeks ago, branded ‘Knight’ (local Chinese brand) had a very beefy frame. The crown was forged aluminium. The frame itself seemed solid. It was a bit on the heavy side at 5.4 kg with the Maxxis CC tyre. Then there’s this other one branded ‘Teliang’ (特亮)which looks similar to the IG but uses proper 42x22x12 bearings, price is about 200 USD:

Unfortunately with this local Chinese brands you get very little info on specs, so there’s no way of knowing what material the thing is made of etc.

Which brand was the frame?

Only issues with equinox is many don’t like the 25.4 seat post diameter and if you get good at trials which usually requires a very good tuck the big square corners of the crown can be brutal on the knees. See the tuck here

Old KH model
Old impact gravity model
Current mad4ones seem to not have any major flaws. The Old KH did break but not as fast as the new one.

To be honest though the breaking doesn’t occur so much from trials only from tricks. You need to be practicing a LOT to end up stressing it that much.

I did still bend the new KH from a smaller volume of tricks however I’m 90kg.

Wow that video is pretty breathtaking, is that unicycle level 2 o 3? :smiley:

Anyway, isn’t the white frame in the video the IG with the thin bearings?
The mad4ones look solid in every way, that could be the answer.

That Teliang might be a Chinese ripoff of the Impact Gravity, though since all these things are made in China anyway, perhaps it isn’t fair to call it a ripoff. If you do get one, a lot of people on this forum will be curious to know how it holds up.

The hybrid unicycle I got was -I assume- made of parts that UDC was trying to clear out of its inventory in 2013. The frame is Impact Reagent, the wheelset was KH20 flatland, and the rest is mostly Nimbus, though I think the seat is some sort of KH/Nimbus joint venture.

Any frame will snap if you are a crazy enough rider. Pinoclean provides details above. The only really serious problem with my uni was the KH Moment hub, which started to creak almost immediately. As I learned from this forum, KH hubs had had this problem for a number of years, but the more recent KH Spirit hub apparently does not. I finally persuaded UDC to give me a replacement Nimbus hub- the same hub that is in the Nimbus II. No problems there, and it’s been several years. The other things that broke on my uni were only after extended periods of heavy use.

It took me months to learn to hop, but that was partly because I started on a $30 unicycle and knew that hopping would destroy it, so I learned other basic skills first. I met one guy who learned to hop before he could even ride, but he had just bought himself a very solid municycle, and I guess hopping was the most obvious thing to do with it.

That is the old impact gravity with 42mm bearings fairly sure. The video is 2013 and the impact gravity came out at Unicon Montreal in 2014

I suppose it would hold up pretty well if it was me testing it since I can’t even ride yet :smiley: The guy who sells ‘Knight’ in China told me ‘Teliang’ is a rip-off of the former; personally I think it’s all BS.

42 mm bearings I assume.

Those Nimbus hubs look pretty decent, actually.

I expect hopping would be relatively trivial for someone who’s previously ridden bike trials, or a pogo stick for that matter. It’s the regular riding that’s completely alien.

Looks like they tried to re-invent the wheel—and made it worse… :facepalm: This sort of thing happens a lot, actually. Companies perfect a product to the point that there’s very little left to do other than sitting back and counting the money, but they need to keep their employees on the payroll so they artificially create work that is not strictly necessary a.k.a. fixing something that ain’t broke. Next thing you know Microsoft kills the Start menu on Windows 8 only to bring it back a few months later, etc. The next revision of the Impact Gravity will no doubt have standard bearings. The current iteration should have been called the “Impact Vista”.

Anywho, I think I’ve made up my mind, mad4one is the way: I like the way they are built, how the company gives buyers plenty of customization options, and the whole company ethos. They do international deliveries and pricing is very competitive. I’m first going to get a cheaper 20-incher to learn on (probably the Nimbus II /w the white tyre), then upgrade to a mad4one when basic skills are where they need to be at.

Yeah, this thread is the first place I ever heard of 32mm bearings. My Impact frame has 42mm. You mentioned earlier that you couldn’t find 32mm on non-unicycle websites. I wonder if that was the point of the company switching over to them- to create customer loyalty by force!

Well, it ain’t working very well, because I was all set to buy the IG and now it’s off my shopping list.

TBH those mad4one unis look beautiful and they are similar priced or cheaper than Impacts and KHs. Their top-of-the-range MADTRIAL-MACHINE costs €499, and their MAD-TECNO 19" is only €429 on sale right now. The Impact Gravity costs €489 and it has the annoying non-standard bearings problem.

My 24" has the new, 32mm bearings. Oh, well, someone has to be UDC’s guinea pig. I have had zero issues with bearings on all my unicycles, including the 32mm bearings on my Impact frame. I don’t know if the issue with the failure of 32mm bearings is due to a fundamental design flaw…or poor quality bearings. UDC seemed to think the design would be lighter and stronger.

The design is definitely lighter, but not necessarily stronger. If it was needle roller bearings then yeah it would be both lighter and stronger, although it wouldn’t take axial forces too well. If you are not doing any kind of extreme riding, the 32 mm bearings are not going to crack or implode, the only issue would be getting hold of them when they wear out which all bearings eventually do.

From the mad4one website (link):

Yeah, that Mad4one website is impressive. If I were looking to spend $600 and get a top-of-the-line trials unicycle, it is probably where I would go. I’m sort of surprised I don’t hear about Mad4one more often on this forum.

My first ever google search for “unicycle” lead me, rather conveniently, to “unicycle.com”, a search result that pretty much sells itself. Now, there are no mad4one products listed on UDC since they sell B2C. UDC is the best know and most popular uni retailer, and after reading so many references to UDC on this forum I came to the conclusion that “if you can’t find it on UDC, it doesn’t exist”.

The other reason is, probably, that their website, “unaruota.com”, doesn’t scream “unicycle” like UDC does—unless you speak Italian, that is—so it’s easy to miss.

Finally, even thought mad4one’s top-of-the-range unicycles are actually cheaper (and, dare I say, better) than the KH and Impact flagship offerings, mad4one’s low-end stuff is more expensive than the really low-end stuff sold on UDC, and many beginners probably choose to get the cheapest to begin with in case they don’t like the sport. That’s the inception of customer loyalty, and the next uni purchase is likely to also come from UDC. It’s just the way most people’s minds work.

Anyway, that’s my analysis… but I’ve been enlightened :slight_smile:

Quick update, I contacted mad4one and they told me to first buy a cheap Chinese uni, learn, then upgrade to one of theirs. Impact never replied to my email. KH did and obviously recommended their own product. Anyway, I felt mad4one gave me the most honest answer so I’m going to follow their advice. I’ve just ordered a black ‘Teliang’ for 1300 CNY (about 205 USD), description says it weighs 5.0 kg with Maxxis CC. Can always shave about 300g by switching to a Monty Pro Race tyre. The 36-spoke eyeletted wheel features 13G spokes (so it should be a bit stronger than the usual 14G). Frame and cranks are 6061-T6 (should be T6 anyway) aluminium, didn’t ask about the rim but I suspect it too is. The thing is made in Taiwa—like most other unis—and all parts come with a lifetime warranty against manufacturing defects. Sounds pretty good, now let’s see how it turns out in practice.

Got one with the black frame, black hub (they don’t do other colour hubs) and blue seat post clamp. Here’s a picture posted by a previous buyer; will post more pics once it reaches me in about 3-4 days.

It might just be the photo but those cranks look really long.

They do 127/135/140 mm cranks, I guess those are 140s.

Yeah, it does sound like Mad4one probably gave you the best and most honest advice. That Chinese thing you ordered really doesn’t seem too bad, and it might be a long time before you feel the need to upgrade. If I were the one buying that uni, I would hope they put the 125mm cranks on it, as those are more versatile, but if you really end up being as focused on trials as you think you will be, then 137 or 140 would be better. In any case, for the next few months, or possibly longer, it won’t matter!

Chris Huriwai uses 125mm cranks. Being a street unicyclist, he doesn’t do quite as much high jumping as a real trials unicyclist, but the jumping he does do, as well as the other stuff, is pretty impressive!

I read your reply just in time and asked the seller to supply the 127 mm cranks, which are only available in black, so with the all-black look it’s going to be a stealthy look! Once I can do basic riding I will get a pair of longer KH cranks from UDC as these cranks have generally got very good reviews round here. Cheers!

This looks like one of the best ripoffs of an old impact gravity that I have seen and may end up being fairly strong framewise.

OK the uni arrived today, first impressions are fairly good especially the wheelbuild feels solid with the beefy 13g spokes. Frame is hydro-formed which is nice.

  1. “Fork” flex: I can pull the fork tips together by about 1cm using one hand. Is this considered normal? Using my Echo 20" trails bike fork as a reference, the same unscientific test results in about 2mm deflection (if that)—in a word: stiff. The frame with no seat post clamp, no bearing clamp and no bearing clamp bolts—so basically just the bare frame—weighs exactly 563g on my digital kitches scales.

Tealiang: 563g (presumed 6061-T6)
KH20: 605g, 7005-T6
Impact Gravity: 572g, 6061-T6
‘Knight’: Don’t know but definitely heavier and stiffer than Teliang
Echo ‘Urban’ 20" trials fork: 740g, 6061-T6

I suppose trials bike forks endure greater stresses than a unicycle frames, hence the added weight, however the Teliang frame does seem a bit too feathery. When I tap with my nails on the metal it rings hollow, whereas my trials fork rings in a way that you couldn’t tell if it was hollow or not without holding it in your hand. If that makes sense.

  1. The seat post goes deep into the neck, I could easily hack off 4-6 inches and the end would still be a couple of inches below the clamp. If I was to shorten it, what’s the recommendation i.e. how long below the top of the neck?

  2. How tight do I tighten the seat spost clamp bolts? The goal is to prevent the saddle from turning while riding the uni.

  3. No crank stops: The bearings are press-fit, and there is no spacer between the inner race of the bearings and the cranks a.k.a. ‘crank stop’. All trials bikes with ISIS bottom bracket have crank stops. Just read this thread: A small space where the axle is visible, should I worry about this?

On a side note, I can’t understand why anyone would want press-fit bearings. Am I crazy or something? A snug fit is sufficient if crank spacers are used.


All three tubes are hydroformed