Future of Geared Hubs?

I am contemplating a geared hub, but I have some reservations:

  1. They seem fragile, still prone to failures, and not easilly repaired; i.e. must be removed from wheel and sent to manufacturer.
  2. They remain very expensive.

Will they come down in price?
Will the durability improve?
Will they be upgraded to three speeds?
Should I wait a couple years?

They will not come down in price if your looking for a schlumpf type of hub.
Because they can not manufacture 1000sends of hubs there just is not a market for it right now and that not changing next year maybe over a period of 10 years

Durability will improve schlumpf can not afford so many breakdowns
so you wil see a improved version of the hub

By using a complete diffrent hub type and wheel there are hubs with 7 or 8 speed in unicycles

If you want big speeds right now dont wait for it but use the material availble right now

I have some projects going on right now trying to make a 7 or 8 speed unicycle.
Hope to speed up the proces in september ( start working at a bicycle factory on the engineering side of it)

  • Price: Eventually, but until lots more people are buying/wanting/making them it’s not going to happen so it may take a long time.
  • Durability: It already has, and that will continue.
  • Three speeds? If somebody builds one. That would be the first step, but a much larger step is to manufacture them. So don’t hold your breath.
  • Wait a couple of years? Depends how fast you want to ride in the next couple of years. I would order one now if I had the extra money. In fact I did have one reserved last year, but canceled because I knew there would be a lull in my road riding after RTL and I was right…

So start saving up now, and when you’re ready there may be more choice, or a better hub, etc. :slight_smile:

These are all valid concerns; I too struggled with my decision to buy one or not. I finally decided to because:

  1. I had a unique, once-in-a-lifetime, opportunity to buy one (I could afford it).
  2. I have some huge MUni epics planned and while all are possible w/o the benefit of gearing, having that overdrive capability really opens up the door to a whole slew of possibilities and will greatly improve the time-line of these planned treks.
  3. Versatility. Right now I’ve got my KH/Schlumpf hub laced into my KH24 and in overdrive on the road it “feels” almost like riding my 36er. At the same time, throw my MUni tire on it and I have my old trusty off-road machine. And I already know it packs well as I’ve travelled quite a bit with this setup.
  4. I know that if I do have any hub issues (knock on wood) Florian will always make good and fix the issue. It may be inconvienant and time consuming but at least we’re not totally left to our own when issues arise. I’ve got my KH/Schlumpf hub built up in a duplicate wheelset so I can swap out and go single-speed if I want and if I do have a hub issue I’m left high and dry while it’s repaired.
  5. Now that I’ve finally tried riding with a KH/Schlumpf hub I’ll never want to ride single-speed again! It is so much fun that I wish I’d gotten one sooner!
  6. As far as durability goes I think the recently produced batch (and upgrades) really improved a great deal over the issues brought up on this forum. If you think about it, it’s been quiet on that front lately. :slight_smile:

So I feel it’s worth the risk if you can afford to buy one. I seriously doubt they’re going to be any less expensive for the long term…

If we can meet up some time you can try mine out to see how you like it?

Hopefully we’ll meet at the Asheville Muni Fest.

I want one, that is for sure, I totally see your point about wanting go faster on my uni, esp when I have the room to open it up. We’re heading to Tsali, that would be the perfect place to use one!

Although several people have made chain geared gunis, the Shlumph is the only design that has 2 on the fly gears. I think a chain single speed guni could be made and sold for a lot less than the cost of a Shlumph hub, but with no 1:1 gear, they won’t win any hilly races. Still, if you live in a flat place, or you want to uni for downhill runs only, the chain guni can run a higher gear than a Shlumph. Maybe Uniskater would make you one for less then 1200 $, plus it comes with a frame. As far as I know these are all homemade customs.

Will Shlumph costs come down ? Only if more units can be made in Asia. You can’t patent the planetary gear set used at the heart of the Shlumph. Harper made one for himself before Shlumph but I don’t know if it shifted gears. So it really gets down to if the shift system is Shlumph patented. If not, the hub could be made for a lot less in Asia, or perhaps Shlumph will grant a license.

My prediction is that there aren’t enough nuts like us that want them, even if was inexpensive. I mean, let’s say KH does a production run in Taiwan of 10,000 hubs and they only cost him 200 $ each. So he could ruin Florian’s day by selling them for 500 $. Then go bust himself if it takes 20 years to sell all that stock. How many plain 36 er’s are sold world wide in a year ?

So rather then see a price drop, we will be lucky if Florian stays in bizz in this tiny market. I predict his sales will drop a lot this year. Partly because of the economy, but mostly because a bunch of 36 riders bought them after RTL, and now they have one. He has a corner on the market and likely wouldn’t sell but a few more at 600 $ then he sells now at 1200$.

There is no chance that the planetary gear system of the Shlumph will go to three speeds. Multi speed systems on bikes and motorcycles use a completely different gear system.

I’m no engineer (“back off man, I’m a scientist!” :wink: ) but if there were some way, either with interchangable parts or something to make these KH/Schlumpf hubs so that they’d be available as they are now for unicycles but also in a free wheel form then perhaps there could be a market in the bicycling realm? I’m not saying as is, but perhaps there could be enough uniformity on the hub internals that they could be re-used inside a different hub body. I know of a number of internally geared bicycle hubs available, and all of those are very expensive, but there is a market there… So a bicycle compatable design could be married to a unicycle compatable design using a majority of the same parts then one would have a market and perhaps more of a mass production could be sustainable? Just brain storming here… :slight_smile:

I’d phrase the question like this: of the people that would purchase a Kris Holm unicycle, how many would be interested in an affordable (e.g. less than or equal to the price of the unicycle itself) geared hub (or equivalent gearing system)?
I’m thinking that number has to be close to 100%.

here is a thought (an expensive one) but could this work use one of these hubs http://www.rohloff.de/en/products/speedhub/index.html its an 14speed internal hub i run on a bicycle of mine the downsides i can see is you would have to run a chain and chain ring as well as the shifter up to a handle bar like the t-7 but i think do with the right enginering and patients to set it up it would work great

There will probably be some production non-planetary gear designs which are a lot cheaper than the planetary design of the Schlumpf; a jackshaft is inherently easier to build than a Schlumpf. But they aren’t shiftable, and it’ll probably be a while before there’s a production model of anything.

Durability might improve; it depends how much effort Florian wants to put into it. I can’t really agree with Foss’s comment that durability has already improved; it seems to me like a lot of new hubs are still failing. It may even be the case that the original Schlumpf was better than the KH/Schlumpf in terms of durability. I wouldn’t hold my breath, in any case.

The Schlumpf design will not work as a 3-speed hub.

I think a Schlumpf hub is a poor purchase for anyone who has fewer than about 5 unicycles.

One of the biggest reasons I sold mine is that fixing a broken one is too much of a hassle. Too much time shipping it to and from. Too much energy unbuilding and rebuiling the wheel. Too much money to pay for shipping and possibly the repair if unwarrantied.

A lesser reason is that I’m way more into riding on dirt than pavement. While there are conceivably rides where having both a low and high gear would improve the experience, most if not all of my rides don’t fit that category. In fact I’ve found that all of my usual trail rides are great fun on a 29er or 36er, and the benefits of gearing up either of those are mostly noticeable on the road–see the first sentence.

In the past year I bought an internally geared 8 speed bike hub complete with cable and shifter for $250. At that price, as long as it lasts at least a couple years I wouldn’t have a problem buying a new one if it broke. If I could say the same for a GUni hub, then I would buy one again. But I don’t see GUni hubs getting anywhere near that price, and only time will tell how durable the newer batches are.

Why must future hubs be geared?
http://www.fallbrooktech.com/Nuvinci.asp

Rumor has it that Fallbrook Technologies is working on a fixed CVT, but there’s no word on when it’ll be commercially available.

I have pondered over several of the problems with the current Schlumpf concept that you have already mentioned, and came up with a solution that I’ve put to Florian. He has politely declined on the basis that he doesn’t want to make any changes to his products at the moment, and instead wants to concentrate on reducing the cost, so I don’t think I’m out of line by mentioning it here. However, I’d be interested if you guys think it’s a viable concept or not.

Essentially, I would propose that the ‘gear box’ part of the hub be separated from the ‘flange’ part. This would mean that you could own one geared hub, but have it easily fit in to several of your unicycles. It would mean it could be returned to base if there are issues with it, without requiring a wheel build. A lightweight singlespeed hub could be fitted to your wheel for certain rides. You could go on a long tour with a 36" wheel, but carry a 24" muni wheel easier for those bit of the tour. If a 3 speed hub, or a 1:1.75 ratio hub is developed in the future, it could be used without much work.

If the ‘gearbox’ and ‘flange’ could be produced for around the same price as the whole hub now, then I’m sure more people would commit to buying one as they could buy a second cheap flange for other wheels at probably less cost than a regular unicycle hub.

As you can see from the attached diagrams, I’m no engineer or draughtsman, but I think it might be clearer than describing it.

I’ll be interested in your thoughts or comments.

STM

hub1.jpg

hub2.jpg

hub3.jpg

hub4.jpg

hub5.jpg

I was one of the first to get the Schlumpf, and I’m currently using my third hub.

It’s come a long way in four years, and no doubt it will improve more if you wait. But how long does one wait? If you need one now, then get it. Otherwise, stick with an Unguni.

I dont’ think they will come down in price anytime soon, unless Florian shifts production away from home and the number of hubs sold increase significantly.

They’re a bit fiddly…I only ever use mine for racing with.

I like that idea…and Im sure it’s feasible if someone could be convinced to build it. You should email Florian…I think his hub could be adapted for this. Just needs to separate the flange from the gear mechanism as you say.

The production design I made would do this. It would be nice to leave the ring gear in the hub when switching but all of the guts are easy to remove.

There was an engineering student on the forum who some time ago proposed a three speed shiftable hub with a design that was not completely irrational. It was to be cable shifted.

I think that may be what Florian does for a living. Before he made unicycle hubs he was making 2-speed bottom brackets for bikes. Search around the Web to read more about them. But those are a separate product (you don’t pedal the wheel axles on a bike) so there’s less crossover than you think.

I can’t agree with that. Most people still consider $500 to be very steep for a unicycle. I can’t see close to 100% of that market wanting to buy a $1000 unicycle with a geared hub. The vast majority of the unicycle market is still interested in the basics, and it remains a much smaller percentage of us that want to push the cutting edge. It will take time.

Other than the fact that you’d need a chain drive, a way to get the shifting control away from the axle to a switch, oh, and the part about how it’s a freewheeling hub, no problem. There’s a reason why the Schlumpf hub was built from the ground up for unicycles.

Granted you’re closer to a lot of Schlumpf hubs than I am, but I don’t think Gizmoduck would agree with you on the new vs. old versions. Yes I have my concerns on the issues with bearing holder tightness and all that, but the KH versions have many improvements over the originals. Kinks? Obviously but I think the new ones are much more strong versatile. Reliability clearly isn’t perfect though, and it’s probably hard to develop the product without the income from lots of sales to pay for all the design and testing work.

I really like the basic idea. It seems simple, and very appealing to a seriously advanced guni rider, who could own several gunis but only need 2 hubs to always be on the road with no fuss or waiting for repairs. Simplify repairs greatly etc. Well done.:slight_smile:

My tiny suggestion is about cost. Maybe instead of splines, 2 or 3 key ways could be cut, perhaps with a few set screws, to achieve a zero slop fit for less cost than machining splines, but I am just guessing.

The version that Ken crashed on was recalled; I actually don’t know of a first generation, v2 hub that’s failed. Scalisi still has his, Seth Golub’s went through four or five people before he sold it. I may know multiple people who has personally experienced more hub failures than the first generation v2 hub.

While I think using the bearing cover as a lever arm is a clever solution, in practice I think it’s caused more problems than it’s solved. Really the tolerances are such that you pretty much have to use a KH frame anyway; it would have been better to use standard bearings, and put a hole in the KH frame for the lever arm.

In terms of versatility, the only real advantage I see of the new design is that it’s ISIS instead of square taper.

It’s probably just a different reference. I call the refer to the recalled hub as the First Generation hub, the redesigned road Schlumpf hub as 2nd generation, and the KH/Schlumpf the 3rd Generation.

I think the main advantage of the 3rd Gen hub is that you don’t need a torque lever, has less play, feels slightly more solid, and is slightly less fiddly in terms of taking off the shifter caps. Having said that, we’ve seen a few bearing failures (even if it was blamed on the frame), I’ve broken a button, and I think you can make the hub slip into freewheel whilst shifting if the bearings are clamped down too tight :astonished: . I’ve heard of a couple of mechanical problems (I think Dustin or Sams hub?), but no further details.