Brand new broken Schlumpf

Is there any news yet? What made the bearings disintegrate so quickly?
I just got my KH Schlumpf hub and it seems it is going to happen to mine too:(.
I think the problem is that there isn’t any part that keeps the rubber seal over the bearings, so they just come apart right away.
I also hear a grinding noise when I rotate the wheel. Is that something to be worried about? Does it mean I got dirt in there already?

Yes that is something to be worried about. Email Florian.

I wonder what the problem was with these two hubs?

I have had no issues with mine so far.

Looks like the bearing shred away some of the powdercoating… maybe the bearing holder was not tensioned enough?

Alright, I just e-mailed him. I just really don’t want to take the wheel apart and send the hub to Switzerland now! That would be a real bummer. I’ve been waiting for it way too long already…

Maybe there is a simple solution for my problem, there is still reason for hope… Maybe I just have to put a better gasket on or so. The grinding noise is only very soft, by the way, so maybe it’s not too bad either. Hopefully… But I’ll wait until I hear anything from Florian until I take it for another ride:(. Damn I wanna ride it so bad! Anyways, I’ll let you know how this turns out.

If something is grinding it will most likely get worse. You are probably going to have to send it back. I’m kinda glad I haven’t invested in one of these hubs yet, even though they have been around for a few years, there are still a few problems with them. Hopefully all the issues will be solved soon. But I’m glad to know that Florian is repairing them if there’s an issue.

This problem does seem very similar to the original poster’s problem, and I wonder what caused it. Maybe a bent frame? Maybe the bearing holders were tensioned too much? Maybe just a simple hub failure?

I would like to know what Florian says, so that I can avoid this problem myself. Hopefully there won’t be another recall.

Good Luck. It’s starting to look overwhelming. I emailed schlumpf couple of times because of my broken crank and to put in an order but with little response. But I just got this today:

Hi Daniel

Florian is on a trip trough South America till the end of January. Since he does not have internet access everywhere it might take some time till you will get an answer. If you do not hear anything from him I kindly ask you to resend your email end of January.

Best regards,
schlumpf innovations gmbh
Dorfstr. 10
CH-7324 Vilters / Switzerland
Phone +41 81 723 80 09
Fax +41 81 723 83 64

Florian will be a busy as a bee when he gets back.

You can just order new schlumpf cranks through

Florian answered my e-mail yesterday evening, only a couple of hours after I mailed him. He apologized for any inconveniences and said he had gotten three very similar sounding complaints so far, and he would analyze the two hubs he has been sent as soon as he’d be back from Argentina in ten days. He also wrote that he has not the slightest idea yet what exactly went wrong with these hubs. But he assembles every single one of them himself by hand. According to him he has been using the very same bearings for over three years now without any problems whatsoever.

So I guess we’ll have to wait ten days at least, until there is any news about the hub failures. Meanwhile I took my geared 26" wheel set out and replaced it with the ungeared 29" one for now…

Just got back from the Panama (Evolution of Balance) expedition. I used my geared hub during the trip and didn’t have any trouble with the bearing cages, but I did notice the rubber seal kept popping off and the bearings were exposed.

My bearing cages originally broke after only 6 rides. I’m very cautious about tension, and my frame isn’t bent, so I think the problem was with the hub. Florian fixed my hub quickly and I was able to rebuild the wheel in time for our trip.

The rubber seal really concerns me. I now check to make sure it’s still in place after every ride.

What side is your gold button on? Mine is on the left side (i.e. I use my left heel to gear up).

I had the golden button on the right side. But I noticed that the rubber seal popped out on both sides in no time at all… So I don’t think it has anything to do with which side one shifts up or down with. I don’t know. So did Florian tell you exactly what was wrong and how he fixed it?

Florian didn’t seem to have an answer for what was wrong. He just said he hadn’t seen a failure like this before. Now it seems like there are 3 similar failures?

Yes, apparently… I would like to fix the hub myself, if that’s at all possible. But I would need some more information first. Riding it in it’s current state would probably make it worse, I guess. Although so far all that happened was the rubber seals popped out, plus the bearing cage showed and kind of popped out too. And then of course dirt could get into the bearings, which could be harmful… So I’ll just have to wait…

What do the bottom bearing holders look like on the hubs you guys have? Can you take a picture and post it – in particular, of the inner lip. I just built up my KH 36 wheel with the KH/Schlumpf hub and realized that the frame had the wrong (old) bearing holders with the huge lip. It is a new frame…so either something was messed up in construction, or UDC switched them out (I’m guessing the latter was the case, since it had Snafu pedals too — but I’m not complaining that much, since I won the KH36 at RTL). Luckily, my KH 20 had the proper bearing holders, so I just used those ones.

I swear…I must be a KH die hard. Between me and Louise (who got my hand-me down old KH 20), we have two KH 20s (old cromo one and new alum one), three KH 24s (old cromo and two new alum ones – both with geared hubs), and one KH 36 with a geared hub, spare KH 36 wheel, spare 24" muni wheel.


Well, I don’t feel like taking it apart now, but it looks the same as the frame part of the bearing holder. So the inner lip is much smaller than the outer one, as shown in these two pictures taken from Schlumpfs website:



I couldn’t locate schlumpf cranks specifically. They had others.
As long as it’s square taper, will it work?

Well…add me to the list of people who have this problem with their hub! I’ve gotten three rides out of my geared KH 36. I hopped on for a short spin in my driveway and the hub seized up while in low gear. The right side (the knurled side) had the bearing seal popped off, and there were quite a few missing ball bearings — some of which MUST have slid into the hub and caused it to seize.

Now, I’ve had enough of the hubs to know how much pressure to use, and I definitely didn’t over tighten it. Maybe these outer bearings are simply too small?


Order the Prowheel alloy cranks, they have those in 152mm, and that is what a few riders of the old schlumpfs have been using and have had no problems with.

Oh no! This is bad news, I am getting scared that I will have to return my hub now if there is another recall put out. I have put over 250 miles on my hub with no problems so far, so hopefully it will be fine(since if my hub was problematic I would have noticed by now). I am curious to hear what the problem is though since this is the fourth account of this happening now.

Thanks again:)