When to expect the disc KH cranks

Ugh. Now my project list has been expanded beyond a home built 36er commuter bike, to now also include a geared 36er Penny Farthing. Although I’m thinking a more standard internal geared hub with freewheel might be a good adaptation. . . Gee thanks. :smiley:

But that does appear to answer the question about KH cranks and d’brake.

Anyone have any pricing info on the new cranks?

i am guessing around 100 mark…

Assuming priced like the original prices UDC shows for KH Moment cranks, $96 for single hole, $110 for dual hole.

I am wondering will the disc be on the right side or left? Since the Triton frame has the disc brake tab on the right side. If the KH goes to the left side the I would have to run the D-brake mount to adapt.

Right side for sure
Frame is modified at bearing holder by 2mm because of disc bolts clearance but I don’t know if it’s possible to modify current frame and I don’t want to change it :frowning: Additionally, I don’t know if caliper is attached to frame by a welded bracket or on bearing holder as Nimbus D-Brake style which is more accurate solution than welded bracket

All the pictures I have seen of the KH disc cranks have shown the disc on the right side and Kris has posted that the KH frames will have the disc tab on the right side.

I didn’t remember that

So will need to change my frame if still relevent information :thinking: But not sure as Roger Davies told me recently that they realized the bearing holder (as D-Brake and Mountainuni) is much more accurate than a welded tab on frame from industrial process point of view.

Wait and see, not long to wait as release is planned by next month

Ahh got to love the big wait!

I’ve heard that the D-Brake was designed for the Nimbus internal disc if used on the left side of the uni, or for the KH external disc if used on the right side.

fify

Brake mount adaptor

In expectation of these new cranks I have been looking at disc brakes and the d’brake bearing cap

My understanding is the d’brake is IS spacing.
Most brakes seem to be post mount spacing and I need an adaptor

Should I expect said adaptor to be included when buying a disc?

Secondly how is this adaptor revered to. Is it a ‘IS to post’ adaptor. Or conversely a ‘post to IS’ adaptor
I was planning on buying from my LBS and have the guy there sort it out but he has refused to sell a single brake and only sells in pairs. So will be using
Chain reaction cycles

The frame mount would be necessary for use with the schlumpf hub. The Dbrake bearing mount would not work because of the specialized schlumpf bearings.

The D’Brake mount would work just fine with a schlumpf after a quick date with a belt sander. Or if you don’t like modifying things you can use a MountainUni UCM which has a thinner profile and should bolt right up.

I believe you want a standard rear adaptor for whatever size disk you are using with the D’brake or UCM. I can’t remember for sure though as I just brought the unicycle in to a shop and asked for a adaptor that would fit.

Adaptors are often included with disk brakes but not always.

Yeah Kris had told me about the sanding of the dbrake. And I hope he won’t mind me quoting a short excerpt with regards to using the dbrake with the Schlumpf hub:

[I]“One caveat though, about using the disk brake on a Guni: as you know, the knurled housing is braced against turning by being clamped in the bearing housing. Because a crank-mount disk brake runs the braking through the gearing system, it may place additional rotational force on this interface, depending on the rider and the riding style.”

[/I]
So I would definitely NOT want to use the dbrake for my G26er, and would only consider the frame mount.

Terry:

Either way if you are using a crank mounted disk with a schlumpf the braking forces are going through the gears. From the hubs perspective you are just adding back pressure to your cranks. It doesn’t matter where the calliper is mounted.

It’s primarily the fact that there would be uneven pressure on the specialized schlumpf bearings, especially the knurled bearing, given the fact that the dbrake cap must be tightened all the way down on the leading side, leaving a big gap on the other side. And either bearing be damaged by over-tightening the bearing caps. This is one of the main reasons why the frame mount would be much better. So in this case, I defer to Kris. :slight_smile:

I received my brakes with adaptator but if yours is delivred without, you can use this one http://www.chainreactioncycles.com/Models.aspx?ModelID=69495

Terry, this is a non issue. If the brake torque is so significant, then the frame will twist under braking anyhow, causing uneven pressure on the bearing cap, which will cause the same non problem that is worrying you.

For a counter perspective, Josh at UDC said that one of the reasons they went away from frame mounted disc brakes is because it was twisting the frame. He added that by placing the brake caliper on the the bearing holder, the torque was more controlled and LESS of an issue because the wheel/bearing moves with the bearing holder unlike the frame which would be twisting above the bearing holder.

Now back to your scheduled program…it’s June already, when are the cranks coming in??

Your quote from Kris does not at all address the issue of frame vs bearing cap mount, so I’m not clear on what you’re deferring to?
Speculation aside, I hope and expect we’ll get some guidance and instructions on use of the disk-mount cranks when they are released.

Not to mention, you can put the knurled bearing on the side opposite the D Brake if this is such a concern.

The D Brake adjusts diffently than a normal bearing cap, but it is designed to do so by having one side “set” while the other side is used to establish bearing pressure.

In all liklihood, it is a BETTER way to manage bearing pressure since with a typical bearing cap, both sides of the bearing cap “gap”, whereas the D Brake has one side set with the upper and lower caps flush, thus it reduces bearing movement and is MORE secure.

I think UDC should design all of their bearing caps so that one side is adjusted flush and the other side is used for tensioning, it makes more sense to adjust tension from one side vs two.