I have been using a Mountainuni disk brake system for about 8 months now and figure it is time to write a review. For the quick version skip to the bottom
First impressions when I opened the box were not really all that great. They were poorly packed and didn’t have an even number of spacers on all the bolts. The packaging has since been improved and I think the spacer thing was an anomaly (I had the right amount, just not evenly spaced).
There was considerable confusion about what adaptors were needed to make the MU disk system work with various frames. I had a custom Triton frame with disk mounts and Hayes Stroker Ryde disk brake with a 180mm front/160mm rear adaptor. I was able to make the adaptor work flipped upside down but it wasn’t ideal. I found out later that I needed a 160mm front adaptor for a welded on mount.
Once it was set up and I was able to go for a ride all that tinkering and fooling around with spacers suddenly felt worth it. It was the buttery smooth braking action I had been looking for.
I set up a few wheels with disk cranks to work in the frame but was unable to make my Schlumpf wheel work with the flared out Triton frame (though it worked in a KH frame) It was great to be able to switch wheels with ease and not have to move the brake. It was also great to be able to have a brake with my 32" wheel since there is no frame with brake mounts in that position.
I moved the Hayes brake to my 36" frame with a UCM adaptor and setup a Shimano M775 brake on the Triton for CMW. Unfortunately I could not mount the Shimano brake lever in my preferred position on my muni bar so I used the 36" frame with Hayes and UCM with my 26" wheel for the weekend and had flawless performance (once I got clearance issues sorted, ended up filing down the pad retention pin to eliminate rubbing)
I used the Shimano M775 on the Triton for a very short period of time and had much better power than the Hayes Ryde but swapped the brakes to use the MUni bar on the Triton.
I did fade out my brake while doing “Braile” near Sant Cruz and crashed pretty hard bending the left (non disk) crank. I was disappointed but not all that surprised that it bent since I had drilled a few extra holes in the cranks for multiple crank positions.
I appreciated a little bit more power from the M775 brake on the 36 but after a few good descents the brake developed an awful shutter and the disks seemed to be getting gauged by the brakes leaving distinct groves. I tried a few things and ultimately fixed the problem by changing to “organic” pads instead of the metallic pads that came with the brakes.
The M775s with organic pads work great and are absolutely silent when braking which is nice. The groves in the disk left by the metallic pads seem to be smoothing out, and modulation is better than ever.
The disks seem to be a tad wider than the standard disk. This is probably a plus in the long run as they will last longer that way but it is hard to set them up so they don’t rub. I also wonder if the steel used is a bit softer than standard as I quickly wore groves in the surface with metallic pads in the M775 brakes.
The disks are built pretty beefily. The one on my MUni took a direct hit on a rock during a crash and it was just fine, a standard disk probably would have bent from an impact like that.
I have multiple sets of SINZ cranks most of them with extra holes drilled in them for multiple pedal positions. I would not suggest doing this as the SINZ cranks might be strong enough out of the box they get flexy with extra holes in them and can bend at the new pedal hole. I have 4 sets, bent two (but both were multi-drilled)
The cranks themselves feel good with nice Q (same as KH) and are a very nice shape for shifting on a schlumpf hub.
The bearing cap mount in pretty ingenious. I think it is too flexible for use with metallic pads in M755 and equivalent brakes. It works great with the less grabby organic pads though, which have a better feel anyway.
It is too bad you need to take the calliper off the UCM to get the wheel out but it is not a big deal if you don’t take your wheel off often. The UCM works with a 180mm front/160mm rear adaptor.
Hayes Stroker Ryde brake
Fairly weak brake that lends itself well to unicycle use. Doesn’t have great power but is very smooth and has good modulation. Has a 2 piece clamp on the lever mount which allows you to mount it anywhere you have a strait piece of 22.2mm pipe without having to slip on.
Shimano M775 brake
This brake has much more power and great modulation if a bit grabby on initial braking with metallic pads. Too much brake for the UCM on a 36 with the metallic pads but when “downgraded” to organic pads they were buttery smooth.
The clamp on the lever is sort of bulky and might prevent you from properly mounting under the saddle.
[B]Overall the whole system works as advertised and you will be able to experience buttery smooth braking on your unicycle without having to resort to re-building the wheel with a disk hub. (and you would need a UCM or weld on mount anyway).
It can be a little bit fiddly on initial setup but well worth the effort.[/B]
Overall I give it 4 Stars.