Mountainuni Disk Brake Setups

Hey guys there has been a lot of questions about what works and what doesn’t with the MountianUni disk brake system. I figured it would be a good idea to get a database of who is using what (like the Schlumpf serial numbers thread) so we have a better idea of what works and what doesn’t.

I wish I could start this thread off with my experiences but I have yet to install my set.

Lets see what you got, what works, what didn’t work and why.

I am not affiliated with MountainUni in any way, just an enthusiast for outboard disk brakes on unicycles.

my three wheelsets:

downhill 26": KH rim, KH hub, 3.0 tyre, 135 cranks
CC 26": Mavic Rim, mad4one hub, 2.4 tyre (not the one on the pic), 155 cranks (will change as soon as possible)
CC 29": KH Rim, schlumpf hub, 2.5 racing ralph tyre, 155 cranks

brake: shimano slx, changed know to the XT, both wor very good.

no problems with all setups (i’m riding most the downhill setup, also for uphill :wink: ), just the pads wear down quick because the disc gets pretty hot, guess i should brake less :slight_smile:

i love my disc brake system!

Turtle, are you using a spacer between the crank arm and hub on the Schlumpf axle? If so, is it a 6 or 8mm spacer? How well do the shift buttons work in the Sinz cranks? Have you had any issues braking while using the Schlumpf hub?

I don’t know if I should chime into this thread, but these are questions I am curious about myself, not having a Schlumpf hub to test thus far.

schlumpf hub: on the right side (disc) i use a 6mm spacer, on the left side none…

i didn’t use this setup very often, but i had no troubles to shift, also no troubles braking.

Thanks for this info, turtle. I’ll trying to set up a disc on KH/Schlumpf very soon. I guess I need to place an order for a 6mm spacer!

Dreaming of 36” (KH or Triton) with a Schlumpf hub and MountainUni’s disc brake

I own a 36” Nimbus Impulse (disc brake) with Shadow handle and truly love it but I really wish it were Schlumpf compatible. My dream unicycle would be a 36” (KH or Triton) with a Schlumpf hub AND MountainUni’s disc brake system. I switched my cranks from KH 125/110’s to KH 165/137’s because the hills of Kentucky require leverage. The problem is that my average speed on the 10 mile loop has gone down from 10-12 mph to 7-9 mph. Thus the need for the Schlumpf hub to use long cranks and still reach 10-12 mph. As for a true need for disc brakes, I must admit, running the 165 hole, I don’t use my brake nearly as much anymore but when I do I am very thankful for the butter smooth modulation. I ride mostly roads, sidewalks, and bke path’s (Louisville is 20% finished with the 90% funded 100 mile bke path loop that will put us in top 10 cities for b*kes by 2015) so I am pretty set on keeping my wheel size at 36”. Although, I have been itching to get back into MUni (Louisville is also home to endless miles of MTB trails at Cherokee park) and the UDC is supposedly coming out with it’s 26” Nimbus Oregon (disc brake) that will fit a Large Marge rim and a Surly Larry tire which I think will really improve my chances of enjoying MUni more than I did on my (sold) 24” Nimbus MUni. Or, I could always get a Triton Triple Frame to give me the option of a 29” road tire and a Schlumpf hub that might get me back up to 10-12 mph. Dang, I really like riding a 36” wheel I just can’t find time to get to the trails. Most of my riding is out the door and up the street. Decisions, decisions. Gotta make up my mind soon. UDC’s April container is due in May and my wife has already given her blessing for a new wheel. Should I spend a little (Oregon) now and wait until my 8 year old daughter (can already ride her little 12” wheel for 10 feet or so) or my 6 year old son (won’t try and I’m not pushing) grow into my 36” Impulse at which point I will be purchasing a Schlumpf (hopefully by that time 3 speed) 36” so we can ride together and I can still (45 years old and not getting any younger) keep up? Or, should I take advantage of the green light and go ahead and lay out the big bucks (you only live once) for a 36” (KH or Triton) with a Schlumpf hub and MountainUni’s disc brake system?

The impulse is a beautiful product! (Nimbus is good stuff!) I like the Triton 29er idea the most since you could swap between a 24 muni or 29 Guni wheels each with mountainuni setups for the most versatility. Don’t forget, you could still build your impulse rim to a schlumpf hub and run a Uni-Caliper Mount and get a 180mm adapter for the brake and bolt it all together on the right side of your current rig! double check the bearing cap bolts and make sure that those are 60mm apart center to center and you won’t need to change the frame!

36 Triton Schumpf MountainUni

frame: 36" Triton disc
hub: Schlumpf Muni
rim: Nimbus Stealth
tire: Nightrider
brake/crank system: MountainUni 135mm
caliper: Shimano SLX
seatpost: KH adjustable
saddle: Axel Kästle carbon plate KH freeride cover
handlebar: selfmade from KH 20" frame
fun: incredable:):):slight_smile:

Thanks to
Jeff, Eric, Florian, Axel Roger and Kris.

So, Jogi - you have a 6mm spacer in between the crank and the hub without an issue?

dang! how much does it weigh?

6mm :thinking: - no its three or so, will measure it this evening.

in combination with standart nimbus /KH hub its 6mm.

@ knoxuni:
will balance it…

questions about the MountainUni system used in conjunction of a Schlumpf hub

I have added a (rather long and drawn out) post in the “How to order a Schlumpf hub” thread. Rather than putting you through the torture (I have a lot of fairly fundamental questions about the MountainUni system used in conjunction of a Schlumpf hub) of having you all read it again here I will add a link (below) and ask you to read it when you get a chance. Any advice you may provide would be greatly appreciated. My main question for this thread would be: Would purchasing a 36" Triton frame with the disc brake caliper tabs welded on give my Schlumpf a more durable lower maint setup than purchasing a KH 36" and bolting on the UCM?

hey David,

the Triton frame will be more stabil and durabel - but anyway there are a lot of broken 20" street frames but I never heared about a broken 36" frame so that might not be an issue.
the “technical” advantage of the Triton is the more stiffness what means more of your power goes to movement and less into the frame. But I estimate you won´t feel this on a 5 miles sundayafternoon ride but climbing up a longer hill or fast riding over a longer time.
The stiffness might also be an advantage in combination with the MountainUni disk brake, cause the one side holded brake power will not make the frame stiffer - but I have no experiance in that.
I dont know you but if you are an advanced rider you will probably enjoy the Triton cause of stiffness, otherwise you will like the workmanship.

An other issue may be your wheight and size. If you are not a huge and strong rider may be there is no difference in riding KH or Triton.
( thats not ment insulting - Roger Davies for example is smaller and lighter than me but usually also faster… :wink: )

What works:

Triton tripple frame with disk brake mount
160mm adaptor
Hayes Stroker Ryde brake
Mountain Uni Disk
SINZ cranks (140mm - also tapped at 121mm, 102mm, 80mm)
6mm spacer

I love it

What doesn’t fit:

I tried setting up my Schlumpf wheel to be interchangeable with my other wheel in the Triton frame. I tried a full sized spacer on the right hand side and the crank splines didn’t really engage. I switched to a few really small ones and felt that the most I could get away with is about 3mm of spacer. I then had to move all the disk spacers to the outside to get the disk to clear the frame which has an outward flare. It still did not clear and there was no longer enough room between the disk and the 165mm crank (the 140mm cranks I have on my other wheel seem to have more space at that point but I didn’t measure how much more room I need) for the Hayes calliper to fit.

I have no doubt that I could make the disk work with the Sinz cranks and Schlumpf hub on a KH frame with UBM (or standard Triton frame without the outward flare) but I am going to have to get creative with a file and maybe a slimmer calliper to get the Schlumpf to work on my triton frame with a disk.

We are currently seeking Florian Schlumpf’s approval for use of a 6mm aluminum spacer on one side with the cranks mounted at a low torque such as this illustration demonstrates. This technique has been in practice with a Schlumpf hub for over a year with no ill effects upon the hub. Several Schlumpf hub users are doing this currently.

This is Brian Oley’s Coker! I replaced the original bearing cap bolts with 30mm stainless socket head M6 bolts, and nutted them with star washer nuts. I pushed the bolts up from the bottom and nutted them atop the frame. I needed no spacer between the adapter and UCM, but I did need a 1mm shim under the bearing. The 185mm adapter on the Skeletal brake was set aside and I replaced the adapter with a 180mm Shimano SM-MA f180 p/s. The cranks were square taper and everything lined right up.
I am unimpressed with the fittings that come with the skeletals as they are not compression, but just a hose fitting. the lever has a lot of adjust ability and it has oodles of modulation.

Here’s my Conundrum with MountainUni brake on the 29" wheel. I’m using the UCM with a Tektro Auriga Comp caliper and Sinz 145mm cranks with a 6mm crank spacer. The Larry / Large Marge wheel I currently ride brakeless with Echo 160mm cranks. The Tektro brake has good modulation and plenty of power for single finger braking.

I’ve copied Turtle’s KH T-bar setup and quite like it. Most off-road riding is done with the hand on the grip, but cruising on smoother surfaces with both hands out on the ends is very nice as well.


That’s a sweet looking ride Dave! Like the Black on Black. So how about a review of the Brake and an action shot? I like the turtle bar design too. KH makes a really functional handle so many options. TYKH

it looks really great!

for the T-bar setup: i put it closer to the seat: means i drilled a other hole in this two L-parts under the seat and cut the upper part off so the whole thing is closer… you know what i mean? (the L-parts now broke and i let them make out of steel)

I still have to get a shot of it in action but here are my thoughts of the system:

I waited to see the Nimbus hub mounted disc system before ordering my kit. The Nimbus system looks like a good option but there were a few factors that make a crank mounted system a better choice for me. Even though I was going to be building up a new wheel to use with the brake, the ease of moving the brake to another wheel was a big benefit to the crank mounted system.

My impressions of the MountainUni kit itself are good. Each component was shipped in its own foam sleeve, which was a nice touch. I believe this was a change made based on earlier reviews that said the packaging could be improved.

Setup is straight forward but takes some time. The included spacer washers for the UCM and crank/rotor make the kit very flexible with regards to different crank to bearing spacings. The bolts that came with my 180/160 caliper adapter had non-removable washers that would not fit in the UCM mounting holes so I had to use some other bolts I had laying around. They are button heads so they fit nicely in the UCM and don’t protrude in towards the wheel.

The disc mount and rotor add minimal weight to the uni. I was previously using 150mm KH Moments and the Sinz 145mm cranks with MountainUni rotor and washers added 1.4oz. The UCM weighs 1oz more than the steel bearing cap it replaces.

At this point I’ve been out on three trail rides with the new brake setup. As other users have said, the brake is easy to apply and very smooth. My other muni is setup with a V-brake adapted to the Magura mounts and the MountainUni disc provides better power and modulation, and much smoother braking action. The predictability gives more confidence on down hills, making for smoother and faster descents.

There are some real benefits to using a disc brake on a unicycle and the MountainUni system makes adding a disc brake to a built up unicycle simple and affordable.

Thanks for that, Turtle. Right now the handle setup feels pretty good but ideally it would be closer to the seat. I’ll probably go ahead and do the same mod.