Schlumpf questions: square vs ISIS, new vs used

Ok, I want your honest opinions here. I am considering a VERY lightly used updated version of the square taper schlumpf for my 29" guni. This is going to be a road uni only.
Before any of you chime in with “…a 36” guni is WAY better…" don’t. I disagree.
Also, I know that I probably won’t have a warranty on the used hub but if the price is right, I’m not too concerned.
What do you think? Would a new KH schlumpf be worth about twice what I might pay for the used FSU-2 square taper?

I’m thinking I want to buy this hub!:stuck_out_tongue:

Sounds good man. I don’t know a lot about the geared hubs though…

My only problem is… I unicycle like a fat kid! I am really hard on my unis and while I am not going to be dropping anything with this uni… I am wondering about the durability of the hub.

Does the square taper mean less durable or does it just mean the cranks are going to be less durable? Anyone???

unfortunately square taper is less durable. but then again…as you said you wont be doing any hops or drops so it’d prob be fine.

me personally…i’d want a brand new isis, but i’m gonna wait a couple years probably…when they’re (hopefully) more widely available…

Yeah… in a couple of years, I’ll probably buy another one for a muni set-up


I feel yah man. I might just take up MTBing until geared hubs get cheaper or I suddenly get rich.

NOOOO! Don’t go to the dark side. two wheels are for lazy people, just find steeper, more technical stuff. I have a 26" Surly with the Larry tire and it’s plenty fast for me right now, no need for gears… hence, the reason I am going to build this guni for road riding only :slight_smile:

I know that Nature Quack’s first or second generation sq. taper Schlumpf throws oil out of the hub pretty good. Not sure if that is just part of the older models mojo or more of a wear or maintenance issue?? Jeoff??

Yah. I’m also thinking about going with a 29" eventually. Just don’t have the money for that either. I get a free MTB. :smiley: Probably won’t quite uni, but I may take a break until I get some money up.

alright, I won’t say it then. : )

I have a 36-er and the combo of low gear not being awesome of hills and the heavy tire, rim, tube combo in addition to it being hard to replace spokes etc. Make it an inferior choice for me.

Well now, I certainly never would tell you that your opinion is wrong, but I know that I’d never consider moving my Schlumpf to a 29". I just couldn’t do the riding that I love to do. But when I win the lottery the first thing I’ll do is buy another Schlumpf for my new KH 26". (As an aside, I’m not sure what length cranks you have on your 36" but I know that for the steep hills I prefer 165 mm. And one of my favorite ride starts out with five miles of an 8% gravel road.)
My hub is #00079. It was built around the fall of 2007. So it is one of the 2nd generation square taper pre-KH hubs. The first generation was recalled. What do you mean by “updated version”?? How do you update a Schlumpf? What serial number is the hub in question. Is it listed in the thread about Schlumpf hub serial numbers and their happy owners? (Unicyclists are such geeks. :D)
As Bryce says my hub does leak oil. I really have no idea if it leaks more oil than other newer Schlumpfs. It might just leak oil because I oil it frequently. (about 3 mls of gear oil every month or so) If I followed the standard Schlumpf recommendations of adding one ml of oil every 6 to 12 months then I’m sure it wouldn’t leak much at all. There would be no oil to leak. Perhaps I’m a little over zealous in the lubrication department. Dripping oil doesn’t bother me. I’m happier having a well-lubricated and long lived hub than a house trained hub that dies a premature death.
I’ve put over 3500 km on this hub in the past 2 years. Up until yesterday it has worked absolutely flawlessly. (I was just getting ready to post a “Help me diagnose my Schlumpf hub malady” thread when I saw your thread. Check it out for details.)
With the kind of riding that you do (no drops) then the square taper shouldn’t be a limitation. Even the splined hub can suffer from a broken axle if you do drops, as one unhappy owner of a now broken Schlumpf hub will attest. Personally I ride my hub very gently. I’m a skinny guy who is lucky to put on enough muscle to tip the scales at 150#. I rarely even ride off of curbs. The trails I ride may be steep and twisty but I don’t ride off of drops higher than a curb. So I’m not exactly pushing its limits. Even so, the broken hub stories that I’ve heard about are, with the recent above-mentioned exception, mostly due to failure of the inner workings of the gears or the bearings, not the axle snapping. I would imagine that the gears in the new version are a little stronger than the pre-KH Schlumpfs, but I’m not sure.
So I’d say “Buy it!!!” If you don’t want to buy it, stand aside and let me. Over all, from what I’ve read, the 2nd generation pre-KH Schlumpfs were a good batch. I think there were some issues in one of the early runs of KH Schlumpfs, though. We’ll see how the recently released batch performs.


Thanks for the reply! It’s a second generation hub, that’s all I meant by “updated”. The 29" guni will be my first, if I like it, I’ll probably build a muni with a KH schlumpf.

I don’t mind the oil leaking; I too would rather have a leaky hub than a broken one. I’m going to buy it, I just need to free up the cash.

Sell whatever you need to. Get that hub.
Welcome to the guni club. Your unicycling life will now be divided into two sections: Pre-guni and guni.


Geoff, let me know when you figure out what’s going on with yours.

Geoff, let me know when you figure out what’s going on with yours.

I think Mango was right. I’ll test it more in the next day or two. More detailed explanation to follow in my “Help!” thread when I’m done with patients.

question: i have seen a ton of stuff about ISIS equipment, but i’ve looked it up and i don’t know what ISIS is or stands for. help me out

International Splined Interface Standard

Tirving, If you really only intend to ride it on road, and you really know you won’t be tempted to take it on bumpy stuff or off lots of curbs, you should be fine. Square taper axles only really start failing if you do lots of hopping or drops (or lots and lots of super-hard torque-ing).

I have thought hard on the same question as yours, and passed up two different square-taper Shlumpfs I could have had. I have chosen to go 36", with the ability to ride offroad if I want. I have finally found my own KH/Schlumpf hub! I have to mail the check, then build the unicycle around it, but I’m finally on my way…

Yes, one of the Schlumpf I used as a loaner tended to be oily on the outside. So you wipe it off from time to time; not a big deal. It sounds like you might be buying one of the hubs that was offered to me; if so, the one the seller is keeping is the one I rode in the NZ Unicon Marathon. :slight_smile:

While the 29" is the more versatile, Nathan Hoover convinced me that 36" is where it’s at for road riding. At least if it’s not steep all the time…