Nimbus 24" MUni Disc Brake Upgrade

My custom Nimbus 24"
Disc MUni .

Last year I entered the world of off-road unicycling, purchasing my wonderful 24” Nimbus MUni, a high quality steel framed unicycle built for off-road use. While I haven’t gotten out as much as I’d like, I’ve been having a blast on the local trails, and my Nimbus MUni has never let me down.

I chose the Nimbus steel MUni as a middle ground- it’s solidly built, but lacks some of the bells and whistles of the highest-end Munis. It is, however, built to the highest quality and worthy of any upgrade I choose to throw at it.

After deciding to put a brake on my MUni, I had to decide between Magura rim brakes or discs. While the frame is designed to easily install Magura rim brakes, after a string of messages with UDC, I decided on going with disc brakes. While it’s a bit more expensive to set up, it’ll give me better braking, and I can find spare parts in just about any bike shop.

Since I’m going to be doing some heavy work on my MUni to set it up for disc brakes, I decided to go a little further to personalize it, though you could get by with less and you will have a perfectly good disc brake- equipped Nimbus MUni.

The wheel:

Lacing up the new wheel

The stock wheel is great, but there’s no way to mount a disc on the hub. Luckily, Nimbus makes a great disc hub that matches perfectly with the stock 36 hole Dominator 2 rim and is compatible with the Nimbus Venture ISIS cranks. If you want to reuse your original rim with the Nimbus disc hub, you can reuse the non-disc side spokes, but the disc-side spokes will need to be 2mm shorter. Personally, I took the chance to build a spanking-new wheel using an orange Dominator 2 rim to match my frame, the Nimbus disc hub and black stainless steel spokes.

The brake:

Shimano M396 hydraulic disc brake
with Nimbus D'Brake adapter.

It didn’t take a brainstorm to pick out the Shimano M396 hydraulic disc brake- beside the fact that you can find spare parts in any bike shop, you can check out the rave reviews all over the internet, and they are also about the least expensive hydraulic disc brake you’ll find. To install the brake on my MUni I used the Nimbus D’brake for the caliper, which substitutes the wheel bearing cap, and the Kris Holmes brake lever mount, which I installed under the saddle, capped off with a Kris Holmes Starfighter brake lever extender to make it easier to grab the lever.

Kris Holmes brake lever mount and
Starfighter lever extender.

I’ve only had a chance to ride around the parking lot, but the brake seems strong without being overwhelming. I trimmed the tube to length, so I’ll need to do a full bleeding. Once I’ve had a few rides and learned to use the new brake, I’ll post a full review.

Parts:

Here’s a list of parts I used, those marked with * are extras that you can get by without. For different wheel sizes, just change the rim and spoke sizes. I spent about €260 for everything, however by reusing the stock rim and non-disc side spokes, and eliminating the Starfighter, I could’ve gotten by with €180. I bought everything from municycle.com, except for the brakes and disc, which I bought from bici.it

• Nimbus steel disc hub 36 hole
• 18X 226mm spokes (disc side)
• *18X 228mm spokes (non-disc side)
• *24” Nimbus Dominator 2 rim 36 hole
• 160mm disc 6 bolt mount
• Nimbus D’Brake adapter
• Kris Holmes brake lever mount
• *Kris Homes Starfighter
• Shimano M396 hydraulic disc brakeset
• Shimano 160mm caliper adapter