That really does seem like a good idea. I wish that this issue was fixed on KH or Schlumpf’s side though, I love my hub, but the bolts are just not cutting it for me. Once your cranks are situated it is fine, but I am afraid to even check if the bolts are properly tightened before a big ride bc it further starts to round out the bolt.
I need to order some more bolts now. Hopefully Florian has some ready to ship.
I had absolutely no problems when I tightened the bolts. On one side it came lose but then I used loctite and it is now OK. I must say though that the cranks were first insalled on a standard KH hub, I guess the cranks were seated well during this phase (500 km) so that they fitted perfectly on the KH/Schlumpf hub without the need to put too much tension on the bolts. I am definitely below the recommended torque (I guess it is between 30 and 40 Nm, I don’t have a torque wrench for this range)
oil question
I went for a 10 mile ride yesterday all in high gear and when I finished, there was enough oil running out of the hub that maybe 20% of the hub outer surfaces were oily and it had started to run/centrofuge down several of the spokes as well. There was more oil on the side with the fill screw than the non fill screw side.
Just wanting to hear that this is all totally normal from you other geared uni folks and what I should expect from a new hub. . . . I finished up thinking that the hub needed a device similar in function to a sweat-band for your forehead (Schlumpf diaper?) to keep the oil off the rim and brake track?? Sumthin like this, but hub shaped and not that color:http://s3.thisnext.com/media/largest_dimension/271C2455.jpg
Yes, that last suggestion was a joke, yes?
Brycer1968
Geared 29 pics
I’m starting to really like this now. The custom handlebar tames some of the side to side wheel wobble that seems to happen at speed. It still stays in high gear most of the time for flat land commuting. Love the passing bikes part.
My Schlumpf hub is on the way!
Just ordered my KH-Schlumpf hub. 
On a tip from unipilot69 (who also has one on the way), I ordered from municycle.com (UDC Germany) which ended up having what appears to currently be by far the lowest price (at least when sending to someplace where they don’t have to include VAT). Although it’s been a close call between 29 and 36, I’m going to start with putting the hub in my KH29.
1. Wheel Build Question:
My original plan was to build up the wheel myself. However, I’ve never done a wheel build. While I’m sure I’m capable of doing it, I’d be inclined to do it right and buy a proper truing stand, KH bearing inserts for the truing stand, and a tensionometer. All stuff it would be good to have anyway, but still it’s more cash out of pocket, and my pocket is feeling a little empty right now. On the other hand, my LBS mechanic told me he only charges $30 labor for a wheel build. And I’m confident that it will take me much less time to take it to him than to do it myself (I’d probably drop it off in the morning and pick it up in the afternoon, and the shop is just down the street from my work, so only like 15 minutes of my time).
Is there anything special about building a Schlumpf hub into a wheel? (And I mean just the basic wheel build, not the installation of cranks, which I will do myself.) In other words, is there any reason why I shouldn’t just have the LBS mechanic do it for me? And if I do take it to the LBS, do they need the KH bearing inserts for a truing stand, or should he be able to build the wheel without them (keeping in mind that these little gems cost more than he’s going to charge for the wheel build 
)?
2. Crank Install Question:
I’m liking the idea of using a drilled out M12 bolt for the initial tightening of the cranks. Where are y’all getting the bolts that you’ve drilled out? Local hardware store? I’m not even seeing ISIS crank bolts on the UDC (US) website, but it seems like they should have them, so am I missing something? I’m disinclined to drill out one of my current KH ISIS crank bolts, in case I ever need to send back the hub and want to re-build the wheel un-geared.
Isis M12 Cranksetter Bolt, etc.
James,
I can’t answer all your questions about wheel builds with Schlumpfs (my lightly used KH29 came with the hub already laced into the KH XC rim), but I’m sure others can. One thing I do know is that the Schlumpf manual cautions against over-tensioning the spokes. Here’s what it says: “If shifting doesn’t work as easily as before fitting the spokes, reduce tension on the spokes. Too high tension may result in a deformation of the hub body and can prevent the clutch pins from moving from one into the other position.” Others in this thread have said they simply used the recommendations on the Park tensioning tool for 2mm spokes. Another option you might consider is lacing up the hub yourself, then taking it to your Local Bike Shop (LBS) for professional tensioning and truing.
As to your crank installation questions, I CAN answer those … from recent experience.
Just prior to receiving my KH29 guni I set out looking for an “M12 Isis crank bolt” to drill and make what I’m calling my “Cranksetter Bolt.” Lots of local shops had stocks of crank bolts, but few knew the difference between an M12 and an M15. As it turns out, the M stands for metric, and the 12 stands for the diameter of the threaded part of the bolt in mm. The one local shop that actually knew that bit of trivia just gave me a lightly used M12 bolt which had lost it’s black plastic cap, but still had all the metal bits (i.e., bolt & integrated washer). They even took a caliper to the threads to show me the diameter was 12 mm, which was helpful since the bolt had no other identifying label. The length of the threaded part of this bolt just happens to be 12 mm, as well. (I think this 12 mm x 12 mm is standard for many Isis bike hubs.)
Like others before me, I drilled out the center of the bolt head (on this 12 x 12 bolt) with a 1/4" bit. I was lucky enough to have a drill press at my disposal, and I made a plywood jig to hold the bolt by drilling a 1/2" hole in the plywood, into which I inserted the threaded part of the bolt, before drilling the head of the bolt from from the top. I’m pretty sure this old 12 x 12 bolt was tempered steel, since it took a bit of effort to break through. No big deal though, and the 1/4" drill bit steered well clear of the 8 mm hex socket edges.
Incidentally, UDC-US does sell M12 Isis bolts for $6 a pair (see http://www.unicycle.com/unicycle-hardware/hubs-and-hub-assemblies/isis-bolts/). The threaded part of these bolts are 17 mm long, and the top inside of the hex-hole is stamped with “M12.” (I know because I had a pair on order, which finally showed up after I set my cranks with the shorter “Cranksetter Bolt.”) Although I have yet to drill one of these longer bolts, it looks as if it would be best to drill them from the inside of the bolt, where there is a small indentation that would serve as a “witness hole” to center your drill bit.
At any rate, the shorter bolt (12 x 12) worked perfectly fine when paired with a Craftsmen Torque Wrench and Craftsmen 8 mm hex driver bit. As other have said, you just use the cranksetter bolt to send the crank arms home by cranking down to the recommended 30-35 footpounds (ft-lbs). You then back out the cranksetter bolt and screw in one of the crank bolts supplied with the hub. Change your Torque Wrench bit to a Craftsmen 6 mm, and torque the proper crank bolt to 30-35 ft-lbs. The cranksetter bolt, with its 8 mm hex hole does all the tough work of seating the crank, and the supplied crank bolt just holds it in place.
One slight word of caution. Make sure your cranksetter bolt engages at least 3 or 4 full turns before it butts up against the inside recess of the crank arm. If it doesn’t, you should (as recommended in the Schlumpf manual) give the crank arms “some moderate hits with a plastic hammer to get them a proper seat.” In other words, use a rubber mallet to knock the crank arms onto the splindle far enough so that the cranksetter bolt engages 3 or 4 full turns before it butts up against the inside recess of the crank arm.
Sorry this description is a bit “over the top” but I would have appreciated this much detail before I started whaling on my Schlumpf hub with a rubber mallet.
Good luck with the build and happy guni-ing.
UPD in Utah
(a.k.a. Bert)
Don’t forget that with a Schlumpf hub you need shorter spokes.
UPD - I also saw that note in the Schlumpf manual, which is part of my concern. I think I’ll just print out a manual for the LBS and emphasize that they shouldn’t over-tighten the spokes. On the cranks, thanks for the detail, and I’ve found it very helpful to be able to read about people’s experience on here, so your post should be helpful to others also. I figured UDC would have the bolts, but I looked in the cranks section (they’re listed under hubs), and my search for “bolt” didn’t find them (they’re listed as “bolts”). I’m putting in an order to UDC anyway, so I think I’ll just order from there. And I do have a drill press - can’t really picture doing this without one. I hadn’t thought of the jig idea to hold the bolt, and will definitely be doing that.
Klaas Bil - Excellent point, and I did realize I need new spokes. My LBS sells them for significantly less than UDC, so I’m planning to just keep that business local. Per Schlumpf and KH web sites, it’s 282mm for a KH29 rim.
For ease of reference, here are the spoke lengths per KH web site:
“Spoke lengths: 227 mm (24” rim), 251 mm (26”), 282 mm (29" rim), 362 mm (36" rim)"
http://www.krisholm.com/khu/kh-schlumpf
Isis M12 Cranksetter Bolts, continued…
After writing my treatise on “Cranksetter Bolts” last night it occurred to me that I was missing two important additional bits of information:
and
In search of the answers, and because I wanted to check the tightness of my hub bolts anyway, I took off both buttons and unscrewed the crankbolts. (Incidentally, both were still good and tight, but I’ve only done a bit of riding on the guni since it’s been snowing pretty much non-stop in Utah lately, and I’m chicken to take the guni out in the snow [and salt].)
As it turned out, just answering the first question resulted in a clear insight to the second: The threaded part of the crank bolts supplied with the hub is 17 mm, just like the M12 Isis crank bolts I bought from UDC-US. Hence, the 17 mm bolts from UDC-US would screw in to the inside of the hub splindle no farther than the bolts intended for use with the hub, BUT, being 5 mm longer than the locally-sourced bolt, they would screw in many more than 3 or 4 complete turns before they contact the inside recess of the crank arms when first sending the crank arms home.
Also, the 17 mm long M12 bolts from UDC-US drilled out just as easily as the 12 mm long bolt from my LBS, when drilled from the inside-out.
Bottom line, if you want to be sure you have a cranksetter that will fully engage the splindle while driving crank arms home, buy an Isis M12 bolt with the 17 mm long threads from UDC-US, and drill it out with a 1/4" bit. It will work like a charm.
Cheers,
UPD in Utah
I just joined the stripped crank bolt head club. 
UPD in Utah, thanks for your detailed posts. It’s good to know I can get the 17mm M12 solid bolts from UDC.
But I’m confused about one thing. If I drill out the 17mm M12 and use it to set my cranks, can’t I just leave it in there?
Why do I need to remove the custom drilled bolts and put the Schlumpf provided bolts in?
don’t think so…
Hey MOB,
Bummer. 
That thought occurred to me too, but if you hold up the 17mm M12 “cranksetter” bolt next to the original crank bolt the reason will be apparent: the “top-to-bottom” thickness of the head of the 17mm M12 from UDC is substantially greater than that of the original bolt.
Although I haven’t tested it, I suspect the extra space taken up by by the heads of a pair 17mm M12s from UDC would preclude shifting, since the shift buttons need to have a fair bit of lateral play inside the ends of the crank arms. Also, I believe that the shear strength of the original bolts is greater because the cylindrical walls are thicker – and here’s what Kris had to say about that:
I wonder if it might be possible to make the hex holes of the current bolts tougher through tempering, but I’m no metalurgist. Plus, I’m pretty sure that Schlumpf Innovations actually makes the crank bolts themselves, so the metal has to be soft enough to work.
Be that as it may, by all counts, Florian is very responsive in sending out spare parts to get you back on your Schlumpf-equipped uni. Although I have yet to place an order, I am thinking it would be wise to have an extra pair of crank bolts and buttons, just-in-case.
Good luck,
UPD in Utah
Thanks UPD. The difference in head thickness makes sense.
I’ll try to get some new bolts from Schlumpf and from UDC.
I just wonder why Florian does not use 7mm hex bolts. It would be a good compromise. The only problem may be that it is difficult to get a 7mm allen key, but Florian could provide it with the hub.
I still have got one from the past (20 years ago I needed it to adjust the valves of my car’s engine).
I’ve been thinking about this some more. Does it really make sense that the cranksetter bolt is helping? If I’m applying 30-35 ft-lbs to the original crank bolts, then aren’t they experiencing the same force as the cranksetter bolt? With a properly used torque wrench, there’s no way the force could exceed 35 ft-lbs.
The one difference I see is the duration of the force.
But I don’t see why this would matter.
I’m wondering if this is really the key.
This implies the shifting pin can be pushed somewhat beyond the shifted state, but it will be pushing back. I don’t have my Schlumpf with me at work, so I can’t check it at the moment.
With the crank off, one could probably get a feel for the shift pin’s push-back force by turning the crank bolt on with the socket by hand (no wrench).
I’ve wondered that too. There is some amount of friction between the ISIS teeth, so it should take slightly more turning (i.e. duration) with the “crank-setter” bolt than with the follow-up installation of the Schlumpf bolt. I’m intending to use a rubber mallet, then 35 ft-lbs with the “crank-setter”, then 30 ft-lbs with the Schlumpf bolt. At $6 plus some time playing with power tools, the cost is worth it to me to be super careful with the Schlumpf bolt. If I didn’t have a drill press, I’d probably skip it.
agreed…
Hey uniShark & MOB,
I concur with uniShark’s suggestion to use the “crank-setter” to 35 ft-lbs, before seating the Schlumpf bolt to slightly less than 35 ft-lbs.
As to your source of wonderment – in my experience the first time you mount an Isis drive crank arm on an Isis splindle you have to “send it home” against considerable resistance before it’s properly seated. No doubt this resistance comes from the fact that the machined splines and grooves are never a perfect match for one another out of the box.
What I’ve noticed with two different sets of KH Moment cranks (on both the Schlumpf and a Nimbus hub) is that when you mount them for the first time they often feel seated when you press them onto the splindle with moderate force – but they are definitely not seated in their final resting place. Indeed, you usually have to put considerable torque on the crank bolts to “drive” the crank arms in that last 5-10 mm to their final resting place. (See if you don’t agree with me when first seating cranks on your hubs.)
So, if you can be putting that “extended duration torque” on a readily-available bolt with an 8 mm hex socket that you know will not strip during the process, you definitely will be saving wear-and-tear on the 6 mm hex socket of the custom-made Schlumpf bolt (that also appears to be made of a softer metal)!
At any rate, the crank-setter bolt tool worked well for properly seating 150 mm Moment cranks on my Schlumpf, but please post your observations & experiences seating cranks on your Schlumpfs too!
Kind regards,
UPD in Utah
I guess I will try your method with the cransetter bolt.
So far, I use only the original bolt and did not yet use my torque wrench because I “feel” it would be just too much for the bolt. The negative effect is that I need to re-tighten the bolts after ~ 100 km.
So, I’ll order a pair of spare 8mm hex bolts and will drill a hole in it…
Someone (maybe municycle.com?) should start selling cranksetter bolts commercially, since many people don’t have access to a drill press in which case it would be very difficult to drill the bolts correctly.
I agree
Why should it be difficult to drill the bolts w/o a drill press? I don’t have one and I am too lazy to borrow it from my father. I guess as long as you can hold the bolt in a vise, you should be able to use a standard drill machine. I will try it soon.
Hi,
I don’t understand why a cranksetter bolt have to drilled out?
I mounted lots of KH Moment cranks to KH/Schlumpf hubs (may 50 or 60 pairs) and I allways used a normal M12 ISIS bolt (not drilled out) for the initial tightening of the cranks.
I never got any problems with the shaft!
Cheers
Roland
