Nimbus Disk Brake 100mm hub

OK, Nimbus isn’t sponsoring me (but feel free if you want Roger), I’m just signed up for their Facebook posts.
The latest. Full post here:

The text: “Coming April 2012 Nimbus are releasing 100mm wide disc compatable hubs and disc brake adaptors in Black. This means you will be able to run any disc brake of your choice, using your existing frame and ISIS cranks.”

Lookin good, Nimbus! Awesome you can use any ISIS cranks with it! My only slight concern is wheel strength by narrowing the effective width of the hub. But me thinks I’ll risk it.

Roger, is there any width limitation for the disk brake itself? Pricing info?

Sooooooooooooooooooo stoked for these. Ever since I saw the prototype on Rogers uni and how well it performed in Morzine I’ve been bugging him about them :smiley:

My only concern is possible hub “creaking”, since these hubs are press-fit and not welded. Same thing happened with at least one batch of the new style KH hubs, that also used the splined axle/flange interface. Hopefully UDC addressed that issue and it won’t happen with these hubs. :slight_smile:

So does that mean that your wheel would be slightly offset to the right?

It doesn’t get me very excited since it is a normal hub. Normal unicycle hubs don’t need brakes much as you can only exert so much power into getting them moving. If only it was designed for a Schlumpf hub. Hopefully that will be next.

I am glad to see this come out. I wonder if the KH disk system will be released at the same time?

I think it is great that two major players are going to have very different setups. It will be interesting to see which approach proves to be more popular in 5 years.

My guess would be with a slightly asymmetric dish a la back wheel on a bike. You could keep the wheel central. However would news the wheel build to be done well.
Then again most wheel builds are done in 2s one done with a symmetric dish and 1 asymmetric.
What I mean is most likely my first wheel build won’t be one of these

Yes, the wheel does need building like a rear bike wheel.

The hub has been a long time coming due to our worried about strength of the wheel and the hub. The testing has shown that the wheel strength is not an issue. The hub has the same fixing as the latest generation Oregon hubs and they have not shown any problems.

I am also a total convert! I love riding it and it has changed my riding style and what I will take on. I am a bit of a wimp and don’t like hurting myself but I am now throwing myself down things I would not even consider before.

The system took almost no setting up, it works straight out of the box! I have not that to even tweak the disc once in the 9 months of testing on this model. The only thing I have had to do is replace the pads when they have worn down.


@ Terry: All hubs are press fit other than the welded KH Ti hub. They do this because the hub body can be made from a lighter weight material.

These hubs are sweet, it was just a matter of time before they were built, got one going on my 29er and one on my 26er.

FYI, the new bearing holder brake mounts are going to be black, so if you want green get them while they are still available :slight_smile:

Dishing the wheel is not a new thing, bikes have been dished for years (forever?), you need two different spoke lengths, they build up the same, you can still use your frame from truing.

The Oregon already employs this design and it works great.

I think it’s time to start discussing whether Kris’ model will work better/as well as this kind for non-Schlumpf unis. Also, will you be able to run this hub on Kris’ future frames with the (outboard) disc mount?

So is it me or is it funny that the new Nimbus hub hub is on a KH frame?

I believe there is a new Nimbus frame coming in April as well :roll_eyes:

I’m sure you can make it work with the right spacer combo. An inboard disc is better protected and is closer to the center of mass, so it is likely to pull to the side, but the difference is probably negligible.

I worry about crank creep, so for me the hub mounted disc is superior, but for a Schlumpf the only option is either a crank based disc or a rim brake.

I like the disc brake on the Oregon, it is far superior to a rim brake, esp when it’s wet, it also has a nicer feel and there’s no rubbing. I have no issues with having to adjust the caliper when I reinstall the wheel, probably had the wheel off six times and the caliper stayed in alignment. The bearing holder caliper mount is very solid, I don’t think a frame mount is necessary.

Heard it on the grapevine…

I heard on the grapevine that KH is releasing a similar bearing cup mount for his disc system, rather than a frame mounted caliper. The logic, as it was explained to me, is that this way he doesn’t have to alter the frame manufacturing, and isn’t pigeon-holing everyone into having a disc mount on their frame if they don’t want to use the system. Can anyone confirm or deny? Or maybe we’ll have to wait until the product release in the coming months…exciting times! :slight_smile:

I realize that some folks don’t use brakes, Aspen Mike rides crazy big hills and does it all brakeless, but for those who use brakes they can be a game changer. For me, the biggest benefit of brakes is when I am going down a slight grade, the brake provides resistance as I pedal so I don’t feel like I’m spinning too fast and so my speed stays under control. For steeper downhills, tech stuff, I often skip the brake since it tends to throw me off my line, esp off drops and I have more fingers to grip the handle.

It makes sense, that’s probably why UDC went to that mount, no welding, no mistakes, works with every uni, and it works on both sides.

I had my doubts about the bearing cap mount; having used the original Oregon frame mounted caliper, but after riding it the past couple months I have had zero problems, it is tight, I have no vibrations or wierdness, I would go as far as to say that I prefer it over the frame mount :slight_smile:

Disc brakes do seem to have a tendency to pull to the side, it’s subtle, anyone else notice this?

I don’t have experience with a disc brake on a uni, but I don’t understand how it could pull to the side. The whole hub is being slowed, right? :thinking:

Yes, but it still feels like it pulls in the direction of the brake, that’s why I was wondering if anyone else noticed that. I have unis with rim brakes and they don’t pull, but I notice it when riding a disc hub.

It’s not a big deal, I like disc brakes, they stop way better than rim brakes and there’s no wet fade issues; they also stay cleaner.

I would agree with both UniShark and Nurse Ben.

In theory there wont actually be any pull on the wheel when the brake is applied. The unicycle is a fixed system, so it does not matter where on the spindle you brake. But… that does not help you mind sometimes! :slight_smile:

I have days where under heavy braking I have a pull on one side… although it is always the same side (irrespetive where it is a right, left or duel discs).

I always use my right hand to brake with and I think may be it. I wonder if this is it. Do you think this could be it Nurse Ben?


Probably because it is the most instantly recognizable frame that everyone knows has 100mm spacing.

I think the pulling to the side thing is in your head. With the d’brake mount the braking force is basically vertical so it shouldn’t be twisting your frame. I do get brake steer on my bike though with its horizontal brake force on a flimsy fork.

Crank creep shouldn’t be a problem if you use spacers.

Well, Eric thinks it’s in my head, so maybe it is :roll_eyes:

I never noticed it until I started riding the Oregon, so maybe it is very subtle and a big wheel makes it obvious…

I would never say that it’s a problem, I just noticed it and thought it was odd because it shouldn’t feel any different. I always ride R hand on the grab handle unless I’m cruising and taking an arm break.

Roger, can you say whether Kris’s cranks will have a pinch bolt or be in any way different from the ISIS spline set up the current Moments use; other than the addition of a disc mount of course.

I would love to see the new Nimbus 26 muni complete, anyone have spy shots?

Duel discs?! :astonished:

It was a prototype/science project.

The pulling the to side thing is not in your head Ben!
Eric, the position of the brake caliper, or the mounting method is irrelevant.

The braking torque is put into the fork, around the wheel axis. torque = force x arm, as we all know.
The forces that go into the fork are through the two bolts of the bearing caps, and yes they are vertical.

The force on the caliper side bolt is vertical upwards, on the other side vertical downwards, thus creating a torque. This torque causes this fork leg to bent. The other fork leg stays straight, so the wheel does steer while braking, just like a bicycle fork does.
Even motorcycles with one diskbrake do steer while braking.
The only way to avoid this is to use two diskbrakes.