Thanks for the disc brake feedback, that helps with my decision to buy now or wait.
So, anyone know of a used 26 guni wheel for sale?
Tony - I think it depends on what version of the isis hub you get. He did increase the width of the splines in later models and I guess this allowed other cranks to be used. I tried some nimbus cranks (not sure if they were ventures or not) 1.5-2 years ago and they definitely did not fit on the hub that I have.
I see the KH Moments as being the most versatile since you can get them dual drilled (but yeah, they are heavy as)
The change to slightly wider was at serial # 200 I think. It was only a few mm, but gives more crank clearance and was a good idea.
—Nathan
Curious, do even the latest batch of these hubs still suffer from ‘crank creeping’?
I’m getting the SINZ cranks for my KH29/Schlumpf. I have an older hub, and, as I understand, I’ll need spacers. Does anyone know if there is enough spline there to do this?
Just quoting what kb1 said in the Mountain Uni thread:
If you have a older hub with the shorter spindle I would probably go with the 6mm spacer.
Does anyone remember how much longer the latest version is than the older ISIS spindle?
Check your bearing bolts regularily
I didn’t - and landed on my butt today (ouch!)
I was riding on my 36" and the knurled bearing just slipped at the moment when I tried to reduce speed in high gear.
The uni flew away in front of me. At first I thought that the hub was broken, but later on I realized that it was my own fault - not cheking the bolts for several hundret kilometers.
I now tightened them again with 4 Nm and everything seems to be fine (except for my butt).
I did the same thing. It wasn’t from too loose bolts. I had to grind the bearing housing down just a hair so it could hold the knurled bearing snug enough.
Oh.
But that is not the problem in my case. There is still a millimeter space left between the two halfs of the housing.
Tolerance of new MountainUni.com part…
What do you guys think? I still don’t know if there is enough room for the lower bolt that will attach the disc brake caliper between the Uni-Caliper Mount and the hub shell, but this seems tight too! note the 2.85mm spacing behind the bearing and the part’s inner lip. I’m glad I’m not painting these! They are Made in USA, machined from 6061 billet!
Can you make those bearing caps quick release?
Yeah, yeah, folks poo-poo the “thneeed”, but for a disc brake set up that could use multiple wheels, it is a time saver and would prevent thread wear on the bearing holder bolts.
Seriously, I have a bunch or $$ burning a hole in my pocket, ready to pop for a guni, but I am on the fence when it comes to going disc hub or disc cranks on my exitsing rigs.
Assuming the Schlumpf is not going to be disc compatible in the near future, that makes a disc hubbed frame less appealing to me. If I could have one uni frame set and three wheels (26 x 3.8, 26 x 2.6 guni, 29 x 2.4) I’d be set.
This one thing would swing me.
I saw a design for a hinged cap on the other thread…
Quick release and the Schlumpf knurled bearing holder do not go together; the proper pressure is too specific. Too little and your high gear slips, dumping you on the ground; too much and you ruin your hub. No thanks on that one.
We would be making uni frames if we incorporate QR bearing caps… someday. but I have read a few threads, one recently, that if the cap isn’t tightened between 4-7 Nm on the knurled bearing -you’re on your butt. Tholub is right there! Steveyo is going to be the first to try the UCM bearing cap on his Schlumpf, and I’m sweating the clearances.
Oh yeah, see above 
Seriously?
I realize that the Schlumph is not as durable as a fixed hub, but is it really too fragile?
That comment, if true, makes me very concerned that a $1400 investment in a Schumph hub is a mistake.
Having already broken a $400 KH Ti hub and a replacement KH standard hub , both due to defective designs, all while doing normal XC riding (minimal drops and hopping), I can’t help but wonder if I’m throwng money down the drain if I buy a Schlumph.
It’s very frustrating to have only one choice in geared hubs and for that choice to be so sketchy.
Is there anyone reading this thread who would tell me to “NOT” buy this hub?
If so, please send me a PM, no need to muck up this thread.
It’s not due to rough riding - Kris and plenty of others have been riding hard and doing drops on these hubs for a few years now. They do have a sensitivity to having their special bearings over-tightened though. Like with other unicycles, but more so. You must only clamp the frame cups on tight enough to hold the knurled bearing without slipping, otherwise it is possible to ‘crush’ the special knurled bearing out of shape and it will start grinding badly.
Not hard to avoid, as long as you are aware of it.
Sam
So crushing the bearing(s) won’t damage the hub so much as require a new bearing? How much are new bearings and can they be replaced without returning the hub?
This would all be so much easier if the repair work could be done locally and if UDC was still carrying the hubs. I was told that UDC had so many warranty issues with the hubs that they didn’t want to deal with it any more…
Anyone have insider info on whether the hubs are going to be improved to address durability issues in the next year or so?
Someone may be able to give a more authoritative answer than this, but I think:
No, that knurled bearing is not replaceable without returning the hub. The knurled shell is attached to part of the hub’s insides, as it acts like the ‘torque arm’ in the original Schlumpf. The geared system needs three points of reference, and in the ‘KH’ hubs this is one of them. So damaging the knurled bearing-case (which in turn would damage the bearing inside it) requires some surgery of the hub, back at the factory.
It shouldn’t put you off buying one though; hundreds of people including me own and enjoy them (and treat them with a little care when installing).
Sam
Okay, that makes sense, but it begs the question of whether the previous design with the “arm” wasn’t better, just like BMX or some bicycle internally geared hubs.
I’ll keep thinking on this…
The advantage of the knurled bearing is that you can put it in any frame. But I personally prefer the old design, which was more reliable and less finicky.