Schlumpf hub setup discussion thread

I’m spinning this thread off some comments in James’ My new KH/Schlumpf 36!!!

I didn’t know about this, nor did I find it in the owner’s manual. James, you mean we should shoot all the oil from 1 of the 2 provided siringes through the slot in the crank bolt?

I didn’t do this either. I have noticed, however, a little play in the wheel (holding the frame, the wheel has a slight jiggle side-to-side). The bearing holders aren’t loose, so is this wobble likely due to the cranks loosening?

I also almost lost a button, too, as it had gradually unscrewed. Obviously the tiny button-bolt had loosened. Now I check it more often.

Some hubs shipped “dry” and had a note attached to them saying to push one of two siringes of oil into them. If yours came “wet”, then you didn’t have to do this.

corbin

My hub was an upgrade and came with the note attached. I am sure that new hubs don’t need the injection (unless otherwised noted).

I learned from my past experiences when riding the new set up which is why I didn’t want to add the buttons right away. It is annoying to have to take off the buttons to tighten the cranks and in the first few days you will definitely have to tighten your cranks multiple times.

I simply left the buttons off, rode for 3 miles or so, shifted (with either a button or a small hex key), tightened the cranks (make sure that the shifting rod is pushed in on the side that you are tigthening), and then repeated for the other side. Did that for the first 20 miles of use, and then I put the buttons on.

You don’t have to use that method, but it worked best for me since I knew I would be tightening the cranks a bunch.

Also, more advice: Make sure the hex key you are using to tighten the bolts is a good fit. The original hex key that was sent with the hub to me the beginning of the year was kind of loose in bolt so I ended up rounding out the bolt some (but I was able to get it out before the bolt got worse). I invested in a nice set of hex adapters for a socket wrench and they fit perfectly and I have had no problems with the bolts.

More advice: I have never had any problems with loose buttons, but you should check them more often in the beginning with a new geared set up. I only tighten the buttons with slight force, I always put the long bit in and twist with the short bit of the hex key. It may be tempting to put the short bit in and try to push hard with the long bit, but it isn’t necessary and you don’t want to end up stripping the little bolt like Ken did.

Finally, check your frame bolts/bearing holders. The knurled side should be tightly clamped, but never with excessive force. I only tighten it with a multitool till it is about as much as my hand can twist without a lot of hard force. It is kind of hard to explain. The other side, however, does not need to be tightened anywhere near as much, and should be tightened the same as you would a normal hub. Turn the uni upside and give it a spin, make sure it spins freely like you would expect and doesnt stop after 1 or 2 rotations.

Side to side jiggle may mean that your wheel is out of true. It also may just feel like a side to side jiggle because the KH moment cranks are so heavy and may be heavier than what you are used to when checking a wheel.

Not sure if that helps or if that is the issue.

I mean when I’m holding the frame and wheel still the wheel has a bit of jiggle, side-to-side.

I still can’t exactly picture what you mean by side to side jiggle…maybe it is because I am tired. If you are holding the frame AND wheel still, are you shaking it or something and feeling the side to side movement or are you feeling side to side movement by holding the frame and spinning the wheel?

More comments about setup that I do:

  1. Use blue locktight on the main crank bolts
  2. Always use a torque wrench, to 35 ft-pounds (I think florian said to use 40, but I think that is too much)
  3. Use locktight on the bearing holder bolts, the knurled is slightly tighter than the non-knurled, but NOT cranking it down – just gently tightened.
  4. Give it a good turn on the small allen to tighten the buttons down; that always has worked for me, and I have only have it come loose once (ever), and I haven’t ever lost one (knock on wood!)

corbin

Would bearings be a possibility?

Did you find blue loctite necessary after the cranks had set in place?

With my geared 29er after the first few rides I never had a problem with my cranks loosening - never had to tighten them during RTL or anything.

I guess I will see how my cranks feel after another month of riding and if they are still coming loose I will use some blue loctite, but right now they seem to be on quite good.

When I asked Florian what the recommended torque for the crank bolts was earlier this year he responded with “Tightening torque is 35 – 50Nm” which works out to 25-35 foot pounds, so if using a torque wrench you may want to do 30 foot pounds as 35 should be about the max. I just use a small socket wrench and use hand pressure, and it works for me, but using a torque wrench will be safer.

Interesting! I could have sworn it said 40ft-pounds on the latest directions that came w/the hub. I figure 30 is good enough.

I think the locktight just is insurance. So far, my muni and louise’s muni hasn’t needed any adjustments. I only have a handful of rides on mine, and louise has one on hers

corbin

Speaking of which, is there anything else of interest in the latest directions that is not in the first set of directions that went out when the hub was first released? I didn’t get a new setup guide or a new set of instructions with the returned hub.

He included torque values, but that is it. I think he said to use 7Nm for the bearing holders, but I’ll have to double check.

corbin

My Schlumpf does the same thing. It has nothing to do with frame flex. My spokes are tight, my wheel is true. The bearing caps are tight. As best I can localize the jiggle it is the hub itself. All the bolts on the outside of the hub are tight. I know of no way to eliminate this play. Too bad, because it means that my rim ends up rubbing against the brake pads a little depending on which way I’m leaning.

Any answers, oh wise ones?

Geoff

I think I’m with Fraggle there. Not the bearing holders, but some play in the bearings themselves. Not sure if there’s anything customer adjustable there.

I wondered about that, I guess there would be a note somewhere to say ‘inject oil before riding!’ if needed (Some groovy way to check the oil level would be neat). There was some oil soaked into the wrapping paper when the hub arrived, so I’m assuming it has oil in it and is ok to go.

Great idea for a thread too, bundling all the setup questions into one easy to find place. I’m setting up mine this morning.

FWIW, I stripped my hollow allen-head crank bolts at less than the recommend torque of 40ft-lbs stated in the insruction handbook. I was using a torgue wrench, going slow and had everything well greased.

I think 40 ft-lbs is definitely the upper end.

Thankfully, Florian has sent another set, but I’m out of commission on my geared 29er until they arrive.

The bolts are by far the worst part of the kh/schlumpf hub, I start to round them out after several series of tightening, doesn’t matter if it is a torque wrench or hex adapter for a socket wrench, the bolts just have a tendency to deform.

I ordered a bunch a year ago, and I am on my 3rd set of bolts since owning the hub (which I guess I have had for…over 2 years now).

Any source besides Florian? Seems prudent to stock up on a few

As far as I know Florian is the only source, I am going to order a few more myself.

Any insights why the bolts are stripping / giving in prematurely? Would it have to do with them being hollow? Would the recommended torque of 40 ft.lbs be too high? Would the bolts be of low quality - perhaps on purpose because Florian has to drill them?