I recently purchased a Nimbus D’brake brake mount to use on my KH36 with existing MU disk brake system. UDC/Nimbus have never stated that the brake mount would work for an outboard disk, and when asked they seem to dodge the question by stating that they were designed to be used in conjunction with their disk hubs.
The reason I wanted to try the D’brake is: I have to take the calliper off the mount every time I remove the wheel with the UCM. Not a major problem but annoying for someone who changes tires/wheels a lot.
Here is the differences I found between the UCM and D’brake mount
Mountain Uni UCM
:)slightly thinner, no clearance problems, mine would just barely work with a schlumpf.
Tighter fit on bearing, less chance of movement
taller brake mount arm,
- :)places calliper closer to the frame and makes the brake line go strait up.
- :(caliper needs to be removed when removing wheel
Nimbus D’brake mount
:(wider, would not work with a schlumpf without additional grinding/machining. less than 1mm clearance to spokes (nimbus hub, standard spacers)
looser fit on bearing, easier to remove
shorter brake arm.
- :(caliper is further from frame and hydro line angles out, could get snagged.
- :)caliper does not need to be removed when removing the wheel.
I am actually not sure which one I will end up leaving on the unicycle. I can’t feel any difference braking and they both seem to have about the same amount of flex. Basically the UCM tucks things away a bit nicer but adds a step in removing a wheel.
oh and the bolt holes are about 2mm deeper on the D’brake meaning you need slightly shorter bolts. The 18mm(?) bots that come with it are a bit too long. I replaced them with some 16mm socket head bolts.