from everything I’ve heard from those in the know, the 125mm S-hub is not likely to see the light of day at least not in the foreseeable future. As for that disc mount, which is awesome, I would love to have one of those custom made for my schlumpf! And another option would be the mad4one frame which has tabs on both sides.
I was waiting for a 125mm hub with internal disc too, but as you heard, I think it’ll never see the light of day. Then it occurred to me that someone had made a custom adapter. And yes, it was in this thread, a few pages back. Lobbybopster had a spare one, for an early hub like the one I have. So now I’m installing it in my G29 to make some measurements. And the ultimate goal is to have it in a 32" wheel, with a custom frame (100 mm wide, brake tabs on the left) built by Flamsberium.
And yes, inboard disc are on the left. Simply because the brake caliper has to be to the left of the disc.
I’m wondering if this flange mounted disc brake would put too much torsional pressure on the spokes. And since this would be on the left side, I would be very hesitant to use a Dbrake clamped to the knurled bearing.
I think the spokes will be fine. Mountain bikes have discs mounted that way, and surely during a downhill session, the forces on the disc is probably way above what we’re inflicting on our unis.
Agreed on the D-Brake. Might be too much for the hub - and with a 203mm disc, the dbrake won’t last much! Bouin-bouin told me that an other option would be a Mad4One frame which comes with tabs on both sides.
I don’t think the side the disc is mounted on will make any difference to the stress on the spokes. The braking torque should be transferred through the hub shell evenly to the spokes on both sides (and the wheel is not dished). If anything the change in spoke tension due to the braking should be less on the side with the disc adapter since it has a bigger flange.
Sheldon Brown’s web site has an interesting article on torque transmission in spoked wheels:
Likewise I don’t think that the dbrake is a problem with the knurled bearing (caveat: I don’t have a Schlumpf hub!) I think the force from the disc brake would actually tend to increase the clamping pressure of the dbrake shell on the bearing (think of the dbrake being pulled up by the caliper gripping on the disc as the wheel rotates thus clamping the bearing tighter). The braking force from the disc brake is transmitted directly to the wheel and doesn’t go via the gearbox so it shouldn’t put any more torque on the bearing/frame interface. Assuming it does clamp the bearing slightly tighter that probably helps with resisting braking force applied though the pedals.
Fair enough you will probably be going faster with the geared hub so the dbrake will be under a bit more stress during braking, and if you have a 208mm rotor then Pierrox may well be right in what he says about it not lasting long, but that is probably more of a general problem with the dbrake and large rotors.
As I said, I don’t have a Schlumpf hub and my own dBrake doesn’t get a lot of stress since braking any more than a scuff tends to make me fall off the thing, so this is really just a ‘thought experiment’ and I may well be wrong. 
Thanks for the link DrD, Sheldon is like the messiah when it comes to wheels!
Here are some photos of the final build. No caliper as I mainly wanted to measure the position of the disc with regards to the frame. 4mm. Same distance I measured on my other unis with in-board disc!
Mad4One has caliper tabs on both sides of their frames, I wonder if I can fit a 32" wheel in a 29+ frame…
Sweet!! I agree that the spokes should be fine. As to the D’Brake, I would just add a “Hugo strut” as it’s called named after the inventor on this forum (who sadly passed away in December). I have 2 Hugo struts after braking my D’Brake a while back. On my 36" Oracle with a 203 disc I do lots of heavy XC and I feel fine with it. You can find pictures here on the forum. Mine is less pretty than those here but works just fine (on my Nimbus 26" it’s attached to my rim brake mounts, but on my 36 there are none and I just used a run-of-the-mill pipe mount from the hardware store).
I get my 3rd generation Schlumpf hub next week and will be putting it in a KH29. If I have any major problems getting the disc to fit (I expect to do some grinding), good to know there’s another option…
I’m not an expert on the Mad4One frames and don’t have one myself, but I think it depends on the tire. I know Marko makes them for really wide plus tires like the 29x3.25" Crux. I measured my 29x3.0" Maxxis on a 47mm KH 29 rim to 30.5" and there’s room in the KH frame. I would just write Marko and ask him and he cen tell you right off, as he’s really good with technical stuff.
Hmm… I just looked at the photo on the website: https://unaruota.com/ZC/index.php?main_page=product_info&cPath=75_80&products_id=981&zenid=5rilj0v7is1aio22p8hubv6lj7
I don’t know: In the photo with the Crux 29x3.25 on a 46mm rim (which should be approx 30.8") it looks to me like only about 1" space to the crown, so my rough guess would be a plain vanilla 32" might fit, but anything wide or knobby is going to be pretty darn close… but there aren’t so many 32" tires anyway… the nightrider isn’t so high, so just might be possible…
Oh, just remembered that I’ll see Marko again weekend-after-next at the final stage of the Italian Muni Race in Villanders, South Tirol, Italy, so I will look and ask him.
Laces
I like it.
Another option is a Qu-Ax frame. They don’t currently sell the 36" RGB ones separately but the QX series ones are also 100mm spacing with a disk mount on the left hand side.
I’m using one of their QX frames for my 32" freewheel with internal disk hub.
I do feel like this adapter is a far superior option as it takes the braking stresses away from the gearing, and if you do have some kind of slippage (partial shift, bearing slip), the brake will still actually be effective at stopping the unicycle.
Nimbus Oracle frames are 100mm and have caliper tab mount on left side.
disc adapter
I made this for an early schlumpf #102 sqr. tpr. so I could add a inside frame disc to preserve this fine mechanism.
LobbyBopster
Wait wait what??? What happened? I remember exchanging with him here. 
I’ve reached out to him and he’s already replied: yes it works, they actually made a G32 using their L frame for a swiss lady.
Thanks, the guy who came up with this idea did a pretty good job! 
Interesting! I spoke to David at QU-AX as he’s following this build and he told me they might do a small batch of actual 32" RGB frames in a couple of months - only in green.
Nimbus Oracle frames are only 100mm spacing for 29" and smaller. The 32" and 36" have 125mm width disk hubs.
I measured the space between the disc and the spokes and it comes just under half an inch. Which is too little to fit a current caliper as everyone has switched to dual pistons. Lobbybopster dealt with this problem using a Coda caliper - single piston. I’m trying to find one, but no luck yet. Anyone can point me to a single piston model still in production, that would be great. I’m also looking at the second hand market.
Another option would be a cable operated disc caliper, they seem thinner but I have yet to find dimensions on the web. Looks like the Shimano CX77 could be a good candidate -single side- or the TRP Spyre but the dual side operation could make it too thick.
I read somewhere that calipers for trial bikes are narrower, but then again can’t quite find dimensions out there.
I can also gain a couple of mm by bringing the disc closer to the frame, won’t be enough for a regular hydraulic caliper though.
I measure a minimum space needed between the disk and spokes on my TRP Spyre mechanical caliper as 11/16". Looks like it would be too thick.
Thanks Jim!
I might order a Shimano then, just to be able to measure it! And I can always send it back.
Anyone here has a spare Coda or other single piston caliper, I’m taking it! Even better if you’re located in Europe.
Does Schlumpf innovations ever respond to emails?
I have been trying to get parts for a broken schlumpf hub for 3 months.
Sent him a list of what was needed March 1st, said they would ship it a week later, never heard from them again and wont reply to any emails.
I was pretty successful communicating with Schlumpf through the office manager. Not sure it’s appropriate to copy her email into this thread, but PM me if you need it.
Retro Triton Schlumpf Build with 32h Rim
I’m taking this thread back 10 years with my recent retro Schulmpf Triton 29er build:
Build highlights:
Triton Frame purchased from Sidd here on the forums
WTB Ranger Tough 29 x 3.0 tubeless tire
KH One Saddle and KH bars with brake bash guard.
Milled out KH Moment cranks
Magura Rim Brake with custom handle attachment made from a Magura mount and washers
Schlumpf hub #083 (acquired from Corbin) Laced to a 32h Surly Rabbit Hole rim (great lightweight 50mm wide tubeless rim). I had to do some special spoke lacing, but it works fine so far.
I chose this odd wheel setup because this rim was the only rim brake compatible rim that also allowed for a good tubeless wheel. I prefer rim brakes and my hub is too old for disc. The hub is also likely out of any warranty.
Note - since taking the pics I had to sand the anodization off of the rim sidewalls to reduce brake squeal.
Spoke lacing notes:
Lacing a 32h rim to a 36h hub involves skipping a hole on opposite sides of each hub flange. I decided to skip holes directly across from each other, and to match the hole skipped on both hub flanges in order to even out tension on the rim as well as possible. I chose the most damaged looking spoke hole to skip and the other on the opposite side. I also had to bevel the spoke holes on both sides ( older hub had only 1 side beveled) since skipping a hole causes 1/2 of the spokes to be oriented backwards coming out of the hub.
With the Schlumpf hub and the Rabbit hole rim, Spoke lengths for a 3x 32h pattern were 293mm, and a 36h 3x pattern were 287mm.
I had to buy spokes that varied in length between the 2 patterns (and even had to buy 8 spokes longer than the 32h length). The spokes angling back over the skipped hole (2 holes away from the skipped holes) had to be 295mm. There were 8 of these. The next spokes angling over the skipped holes (4 holes away from the skipped holes) were 291mm. The next set of 8 (proceeding out from the skipped holes again) should be 289mm long (I used 291mm and ground the ends down). The final set of 8 should be 287mm long (I used 289mm and ground the ends down). I chose 16mm long spoke nipples to maximize the threaded length (in case my spoke lengths were too short). The picture of the hub and spokes shows How the angle of the spokes gets more perpendicular to the hub/rim as the spokes crossing over the skipped holes get farther from them.
NOTE - the hub pic has a few optical illusions: None of the spokes touch the hub flanges even though it looks that way in the hub pic. Also, one of the spokes looks damaged in the hub pic, but its not.
This wheel was a little more difficult to true (had a bit of a hop), but now that its done, it seems just as solid as any other uni wheel I’ve built. Time will tell I guess.
