Wilfred Laurier

Hi mechanics group!

I am planning on removing the derailleur gears from my several-years-old rigid mountain bike and installing an Alfine 8 IGH. However, the Alfine has a Centerlock rotor interface and my old hub has the standard 6 bolt pattern. The frame has an IS style caliper mount and I am using an IS-post mount adapter with my Hayes Stroker Trail brakes with 160mm rotors.

Will I be able to install the Centerlock rotor with only minor adjustments of the caliper or will I need to get some other adapter? Or are Centerlock rotors ony for use with Shimano calipers?

Also, do new centerlock rotors generally come with a lock ring included or do I need to buy one separately?

Thanks in advance,
Wilf.

jimc101

Hi Wilf

For your questions

The caliper adapter has nothing to do with the rotor, other than spacing the caliper (from frame or fork) so the brake pad contact area is at the braking surface on the rotor. Almost all current calipers are post mount, and need the IS to post adapter, the 160mm version in your case, would stick with the caliper's brand of adapter, as there can be differences between brands.

As long as you are matching rotor diameters with the caliper (and adapter), there should not be a problem any branded rotor with any branded caliper; there are always exceptions of course, have heard this being an issue with Formula rotors, but not experienced this first hand.

Centerlock (retail packaged) come with lockrings, the higher spec the rotor, the nicer looking the adaptor.

Wilfred Laurier

Great!

This is exactly what I wanted to hear!

JiveTurkey

There are Centerlock to IS adapters to mate an IS rotor to Centerlock hub. But, I'd only go this route if I had an above-average rotor with lots of life left, as the adapter isn't cheap.

fietsbob

There are adapters that are functionally, the centerlock core, that you attach the 6 bolt disc onto..

I have one from QBP 'Problem Solvers', it has a compression screw to snug up the adapter onto the centerlok splines.

mine is on the front dynohub .. FWIW works fine..

Burton

As far as I know Shimano pads use a smaller swept area than anyobe else and their rotors are designed accordingly. Already looked into something similar to this myself a couple years back and the conclusion was not to mix and match brake rotors and calipers.

So my suggestion would be to go for the centerlock / 6-bolt adapter mentioned and stick with the rotor you already have.

Wilfred Laurier

the adapter route is my other option

i was looking at replacement pads
and while xt xtr slx and saint pads are indeed very thin
deore pads look fatter and are also compatible with tektro brakes
so at least some of their rotors
can be used with other brands

although i dont know if they make
deore centerlock rotors

Wilfred Laurier

i think i may go with an adapter
unless i can get a centerlock rotor in my hand to measure
as burton makes a good point about swept area

fietsbob

bigger disc edge, surface and a smaller pad face than that surface should not be a problem.

Wilfred Laurier

right

but i am potentially going in the other direction

burton says the shimano rotors have the smallest surface
which likely means smallest or narrowest pads
and i am using non shimano
hayes
pads
which are larger if shimanos are really the smallest

fietsbob

I've got Avid discs , 6 bolt front, they have a 4 bolt Rohloff disc too. both 160's

JiveTurkey

I can tell you from experience to not let the pad overlap the rotor brake surface area, at least not on the hub-side.

I bought new rotors that had a shorter contact area than my old ones. The new rotor's brake area area is about as tall as my BB7 pads.

The setup worked fine for a little while, then it developed a regular clicking noise. Turns out that the pads sat too close in to the hub, overlapping the rotor's support arms, which have very little surface area. So, as the pads wore down where it touched the brake surface area, the part of the pads that touched the arms didn't wear as fast. When I adjusted the pads closer to the rotor, the unworn area touched the arms.

I had to use various bolt washers between the calipers and frame/fork/adapter to put the pads right on the brake surface and only there.

cobba

I hope that your modifications with extra washers didn't make the pads overhang the outer edge of the rotor.

JiveTurkey

It took lots of trial and error and several thicknesses of washers but I got it just right.

Though, if I had to err on one side, I believe overhang on the outside wouldn't have been as bad because there's nothing there to hit. Though maybe the burr could catch on the edge of the rotors.

For the record, the rotors are Ashima Airotor, newer versions. The brake surface area, at its widest point, is just a tad wider than BB7 pads.

Booger1

These are $10....So simple it actually works!

Wilfred Laurier

where are those sold?
i have only seen the thirty five dollar ones
from problem solvers and shimano

cobba

What about when the overhanging unworn sections of the pads hit each other ?

How well would a brake work if the unworn parts of the pads were pushing against each other ?

Burton

Seen it in real life. What happens is the brakes stop braking and the customer comes in complaining about disc brakes not being all that hot - even though their own mix 'n match build was the source of the issue.

jimc101

In other words, use parts from the same manufacture in possible to avoid this sort of issue. Haven't seen too many issue with rotor width, but plenty with trying to get say a 185mm rotor to work with a 180mm caliper/adaptor, which just wont work.

cobba

Using parts from the same manufacturers won't always stop that problem as Avid's old adapters & rotors are 185mm, their new adapters & rotors are 180mm.

JiveTurkey

Didn't think that far ahead. Fortunately, my desire to get the contact just right didn't let me do this or I'd have a huge lip on the pads by now.

jimc101

Of course that won't, say using an Avid 185mm rotor with a Avid 180mm adaptor will give the same result as using a Shimano 203mm rotor with a Shimano 160mm adaptor - they wont be compatible due the the diameter difference; that really shouldn't even be a consideration, as matching sizes is essential, regardless of the brand.