What wheel size for geared muni for XC?

Unicycles and Equipment
1

I have two geared unis (29 and 36) for road use, but virtually all my offroad riding has been on 24 x 3". Initially on 170mm cranks (I’m talking 2002 here), gradually went down, now on 137 mm cranks.

I moved house not too long ago, and the offroad riding in my new environment is largely cross-country style. There are the occasional slopes, ruts, roots and drops, but more often than not the trails allow for more speed than I can muster on my 24". By way of a test, I’ve been doing some offroad on my 36" with 165 mm cranks (only 1:1 gear), which went not too bad in most places. So I’m thinking of buying/building a faster offroad uni.

If it weren’t for the Schlumpf option, I would probably spring for a 27.5" or perhaps 29". But with a Schlumpf hub, I think 26" would be a more versatile choice. More technical-happy when the trail requires it, faster when the trail allows it.

Now my concern is that 26" as a wheelsize is becoming less prevalent, and tyre selection will become pretty narrow. So I’m wondering:

  • Is 26" in itself a good wheelsize for a Schlumpfed XC uni?
  • Is the 26" wheelsize really dying out in offroad riding (both uni and mtb)? How fast?
  • Would 27.5" in high gear be unusably fast for XC (also in view of my age, and keep in mind I want to continue riding for a looooong time)?
  • I consider a 24" Schlumpf as an alternative option, if 26" would not be future proof and 27.5 is "too fast".

Thoughts?

2

I’m not sure to understand why you want a geared uni for your new trails which are rather XC.
Do you think that a (not geared) 29x3" with 137 cranks would be too slow for your trails?
A G24 in high gear will be, IMHO less good than a 36x150 for example or than a 29+x137. it won’t be necessary faster and it will be less stable, excepted the possibility to shift down for more technical parts, but if I understand well it’s more often a easy XC trail.

I have had my schlumpf on a 26, then a 26+ then a 29+, did some muni with them but I liked it less than a non geared muni, heavier, and I often had accidental up shifts on small drops. And doing muni in high gear… more dangerous than anything else (at least for me).
that’s why I put the schlumpf on a 36er.

So unless you have to ride a long road/path distance before reaching your trail, and unless you want to go really fast on the trail I’m not sur to see the interest of a guni for that.
Some riders are very good with gunis even off road though.

3

So I have to preface by saying that I don’t own a Schumpf.
But from doing lots of 36 XC, I would agree with UniDreamerFR that a 24" Schlumpf offers no advantage over a 36 for XC.
As to the 26/27.5 question: on the one hand it’s a really small difference in rim size (the exact numbers are elsewhere in the forum, but the 27.5 is not halfway between a 26 and 29 but much closer to 26 because of the stupid playing the numbers for marketing). I’m just speculating, but to me 27.5 Schlumpfed doesn’t seem like it would be unmanageable for XC.
As to the longevity of 26", it’s hard to know for sure, but my feeling is that the basic and inexpensive tires will be around for a long long time. Where the difference may be noticeable is in new and high-end tires, where manufactures switched to 27.5. For example, most of the high-end low weight 3" tires are in 27.5 and 29. But for XC you probably don’t need any extra-wide or super sticky thread and a basic XC tire should work fine.
Thus, I think it’s probably a wash between 26 and 27.5". Both would be good for XC.

Although UniDreamerFR does have a good point: if it’s mostly XC and not so steep/overly technical then why would you need low gear? A 36" offers a larger wheel with better roll-over and simply more momentum which are 2 big advantages for XC. 36" with 125s is awesome for fast XC and with the 150s I can handle more variety with more steep sections. Yes, a 26/27.5 Guni will give you a higher gear but without the momentum, stability and roll-over advantages of the 36. On a completely non-technical gravel road you’ll be faster but for XC trails and up-down rolling sections I’m not sure if it’s better/faster. OK, I guess more than anything the Schlumpf would give you a bail-out low gear if you are beat or hit a hard/steep section. Oh, well a 26/27.5 is also much easier to transport and store.

4

Have you tried out the 29er off-road? I’d give it a shot and see if you like that size in the low gear, or you want to go faster.

I prefer a 26x4 or a 29er over my 24, and it’s very noticeably faster. The 26 fat is the most fun wheel I think I own off-road. It’s a steamroller. Make sure you’re not just getting a geared hub because you can.

It really depends on the trails whether I would even use the upper gear. Trails that have technical sections broken up by double-track would be perfect for a schlumpf, but for most of my riding I just don’t see going geared. You know the terrain and your ability.

5

I would vote on a 27.5 geared. Not that much noticeable difference than a 26 and it’s super fun in high gear on easy singletrack.

6

24g

Klaas Bil:

Almost everyone on this forum severely bash any reference to a 24g unicycle.

First, I don’t think we all speak the same language - “Muni”, “XC”, “Downhill”, “Climbing”, etc.

Many here think flat dirt and flat grass are “extreme”. “Rail-to-Trails” is climbing.

The geared build that I enjoyed the most and had the most fun on was a 2008 KH 24" with Schlumpf mountain geared hub and 150mm cranks. I’m not saying it was the fastest or best size for you or anyone else. Just the most fun to ride. If you (and everyone else) are not interested in fun don’t ready any further.

I could shift up or down any where any place at almost any speed with 100% assurance of not UPDing.

I learned to hop and rolling hop right foot back in low gear and left foot back in high gear so I never hit the shift button accidentally (you may need to reverse this depending on which side/direction you choose to mount the hub).

With a stiff 3.0 sidewall tire I could roll and ride ANY downhill I wanted. For a number of years I used the 24g KH in 8 to 12 mountain bike races each year in the Pacific Northwest (we have mountains here). Steep, crooked, rocky, and roots are the the normal (nothing flat, remember it has "mountian in the name). Many times I would roll down very steep single track in high gear, pushing through a squealing brake while in high gear.

I moved up to a 26g KH thinking it was time to grow and get better times (speed). Even after a few years the 26g KH was harder to climb with and enough more awkward I spent less time in high gear. My finish times were usually slower than when I was riding 24g KH. I walked more of the climbs if technical.

Moving up to a 26g KH was a mistake for me. No as much fun l. Not as fast. Not as nimble to turn. Not as sure to mount in odd circumstances (you may recall I ride clippless). Other wise about the same hoping, and shifting. On tight switch backs I ended up hop turning more often. Pushing through a screaming brake seemed a little riskier. If I should have a very bad fall at my age, in a single income family, the consequences seemed worse when on the 26g KH. I suppose the way to word it is I felt like I was “riding the edge” all the time for little gain.

A 29g might be okay for XC but I always picked the 36g if 29g high gear might be useable.

I noticed that as wheel size increases also the tendency for the unicycle to “lope” in high gear increases starting with my 26g in high gear. On the 24g in high gear I just felt like I was getting into the swing of things. My 36g didn’t lope but 29g high gear is the worst for me. Lope is okay but may become irritating for some of us.

Yes, I keep speaking in past tense about geared unicycles. I’ve had seven Schlumpf mountain drive hub since 2009. I’m down to four. I gifted the only one still functional to a good friend while it was still new in the shipping box. The rest have all been literally wore out, been returned for warranty, or failed/broke. Two are in the scrape heap. Repair parts would exceed 50% of new replacement cost IF I could get someone to sell them to me. Even more to ship both ways and pay ridiculous tariffs. The remains two are still on vacation in Switzerland starting there second ski season. I’m beginner to hope I never get them back. If I do, one will go back in the 24" KH.

Are you wondering what I ride in downhill, mountain bike races, and cyclocross now without any working geared hubs? My 2008 KH 29" with a 2.4 and either 125mm or 150mm. I ride the 2009 KH 36" with 110mm or 125mm for XC, Gran Fondo, and road.

If you are still reading this you must be looking to have fun! That is what I feel should influence your decision. Not anything I like. What will bring the most smiles on your face.

Enjoy,
Joe Myers

3 Likes
7

Yeah but your are bungeejoe, when you’re saying something is not that hard it’s like superman saying “comme on guys, flying is easy” :wink:

I agree with you on at least one point, according to my only ride on a G24 compared to my experience on G26, G29 and G36 (which is nothing compared to you), the G24 didn’t felt as tricky and haunted as the G26 (in high gear).
Otherwise I find the G29 more natural (still in high gear) than the G26, and I find the G36 more natural than the G29.

Rolling hops in low gear with one foot in front and in high gear with the other foot, wow, how’s Lois Lane doing by the way? :roll_eyes:

8

Lois Lane (Lanaboos)

It’s a little off topic but hopefully no one will mind.

Thank you for asking. Lanaboos is working through permanent disability issues. Four years ago she wrecked at Steven Pass Bike Park on a trail named Bonecrusher resulting in severe TBI, five compression fractured vertebrae, clay shoveler’s fractured neck and forty plus stitches in her face. When I found her I knew life will never be the same for either of us.

Joe Myers

2 Likes
9

Well, It was certainly a bit clumsy from me cause I wasn’t referring to your real honey but to the imaginary character lois as a way to compare you to Superman.
I wouldn’t have used any humorous sentence to ask you about Lanaboos since I was actually aware of this tragic story.
Indeed I was afraid my joke could be understood this way, and that’s exactly what happened. My bad. Sorry about that.

10

I was not offended. I found your reply humorous. I don’t see my self as anywhere near a super man or expert unicyclist. But my wife often refers to me as “her” Superman. Thus my reply referring to her as “my” Lois Lane.

Me bad,
Joe Myers

2 Likes
11

Lots of nice comments already. However, I just want to quickly comment one point that was overlooked :

Short answer : no

Long answer : 24" is supposed to be dead in the MTB world but there is still enough tires to cover the uses we have with uni (not great but good).
So with dozen years worth of 26" MTB sales, there is still a huge amount of bikes out there and then market for tires.
Yes, it may still mean that not every new tire will get all possible 26" equivalent or it will not get every “innovation” but there will be tires
:smiley:

12

Being new to this, if I wanted a geared muni, 24" seems to be a practical and versatile size. Thought that size would be great in rough and steep terrain, then decent speed of a 36" on flatter stuff. Why would people be down on that size?

13

It is maybe because the size as regular muni is no longer popular now there is good tech on other sizes. And to be fair, 24 is wonderful when doing mountain downhill whereas most of the riders ride flatter trails (not everybody leave near Mt Washington or Utah/Colorado mountains).
And last nail in the coffin is the disk brake that helps have more control on bigger wheels than cranks alone when going down.

My 24 is geared and I am happy with it. The point is that your setup suits you and make you happy so you ride it. And if it is not perfect, you can still put the hub in a bigger wheel (cost of rebuild is far less than the hub anyway :smiley: )

14

I don’t own a geared uni. I value the simplicity of the direct drive and also I can’t afford one.

However, in the hypothetical world where I won the lottery despite not buying a ticket, I would choose the wheel size for the most difficult sections I expected to ride and gear it up for the long drags in between.

Then it comes down to preferred riding style, local terrain, and tyre choice.

I think a G36 would “only do one thing well”.

I think an ungeared 24 handles better on tricky off road than an ungeared 36.

A geared 24 would plod through most things in direct drive and go reasonably briskly on the boring bits between.

If I had only 1 uni from my current fleet, I’d agonise and eventually choose the 29 for its versatility, accepting that it was a little bit slow on the road and a little bit unwieldy on narrow slimy rutted trails. Therefore, a 27.5 with a gear would combine the best of both worlds - roughly as fast as a 36 when needed, almost as nimble as the 24, and with reduced risk of pedal strike.

15

All good info here. And it highlights the main problem of the only available geared hub: the gap between sizes. The 1.5:1 ratio is a bit large and so whichever uni you put a geared hub into, the gap will always be a bit too big to have something perfect in high and in low gear.
In an ideal uni-world, we would have a three gear hub with an extra between those too. Even two speed with 1.3:1 high gear would be more universal I think.

But, the same way there is no such thing as an ideal uni for all, there is not a universal geared uni.

So in the meantime, let’s enjoy and ride what we have!

16

I’ll second that.

17

Haven’t given geared hubs much thought yet, as still in the beginner stage. Still having mixed feelings about the idea that disk brakes are now considered a necessity for serious riding. Something else to break and wear out that needs maintenance. Then I saw the cost of the schlumph hub is around that of 2 high end brake equipped unicycles not including wheel building, and read that some folks have worn out more than one.

I was attracted to unicycling for the space saving hardware simplicity and significantly lower cost than cycling and motorcycling among other reasons like improving balance and learning a new skill. So I think I would also rather buy a pair of new unicycles in different wheel sizes. Not sure the outcome of having an UPD on a geared 36 while going as fast as possible would be particularly enjoyable, but don’t know all the details yet.

I have some background in moto trials, so I am not into speed, and used to enjoy the challenge of analyzing and conquering rough terrain. I anticipate getting into Muni and Trials as I progress. Others into speed might have a different perspective.

18

My Schlumpf is currently installed in a 19" trials unicycle. My plan is to become comfortable using the G19 before installing the geared hub into a larger wheel. I have had some pretty fun rides on my G19. I’ve achieved greater speed on the G19 that I ever did on my 29" unicycle. I took it on a few muni rides, and it was not bad. I swapped out a seat with bar ends, and that helped me plow over obstacles without having the small wheel kicked out from under me.

My struggles with the Schlumpf are as follows: 1. It adds significant weight. 2. I have had continuing problems with the cranks/crank-bolts coming loose. 3. Sudden, unexpected shifting is really not fun. Concerning this last issue, I think the G19 is more susceptible to random shifting to the extent that the rider is more likely to turn the unicycle suddenly, causing the heel to inadvertently push a shift button. I tend to initiate sudden turns with my hands on the bar ends, rather than my feet, resulting in the unicycle turning and the feet shifting relative to the pedals. UPD-City. I spoke with LanceB about unintentional shifting. Lance has a G32, and he told me he never accidentally shifted. I couldn’t believe it. Either something was wrong with my Schlumpf, or my feet are all over the place.

Anyhow, once I get more comfortable with the G19, I’m going to install the hub into a 24" unicycle. There is hill climbing in my neighborhood I can just barely do on my 26" muni, so I figure, with a 24" and the added weight of the hub, maybe I’d be able to ride the same hills on the G24 in low gear.

If I had to do it over again, I’m not sure I’d buy the Schlumpf. I don’t exactly have buyer’s remorse, but I recognize now that the geared hub adds a whole bunch of complexity to the setup. I wouldn’t recommend it for a beginner.

19

The simplicity is still there. No one else should define what you need for what you consider to be a serious ride for you.

This is an aspect of what we were discussing previously: one group of people encouraging another group to feel that their preferred level of complexity is necessary for other people when it isn’t.

The seriousness of a ride is related to the sense of achievement at the end, which in turn arises in part from the difficulty, and is very personal. The overweight 50 year old may consider 5 miles of smooth road serious and the fit 24 year old may regard 10 miles of cross country as no more than a training ride.

If a brake makes a given ride significantly easier, it makes that ride less “serious”. If it makes an otherwise impossible ride possible, it becomes a real benefit.

I am probably not in the top 50% in this forum in terms of technical ability or achievement., but I refuse to accept that my biggest achievements are somehow devalued because I might have done more or better if I’d had a brake, and certainly not because someone else considers a brake essential.

Apart from which, we should be cautious about using “serious” too often in connection with riding a one wheeled bike for fun.

20

I think unicycling should start out as a low cost endeavour requiring basic but sturdy equipment, a high level of skill must be developed just to do the most basic fundamentals.

As far as I am concerned, being able to freemount, ride forward straight and turn properly, idle and go backwards without falling down on flat ground requires a high level of skill and physical fitness. This can only come from a significant investment of persitent time and effort.

There are plenty of skills to become proficient in long before the use of brakes, gears and other gizmos like electric boost add significant cost while taking away the simplicity of the hardware.

Brakes are affordable for most unicyclists. I am disspointed in the high cost of the Sclumpf hub, but it seems to be the only sensible option currently available for those that want more gears.