Rim for mountain bike for disk brakes

I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

On 7/4/21 8:59 am, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.



Practically any 26" MTB rim will do. The difference between rim brake
and disc brake specific rims is usually that the disc brake version
doesn't have a surface for rim brakes to work on - but it doesn't matter
if you use a rim designed for rim brakes on a wheel with a disc brake.
In fact you could use such a wheel in either rim or disc brake bikes!

Braking forces act from the hub through the spokes to the rim and tyre
with disc brakes. Make sure you have at least a 3x spoke lacing pattern.


How will you mount a disc brake calliper to what I presume is a rim
brake equipped bicycle frame?

--
JS

On 4/6/2021 5:59 PM, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.


Doesn't matter.
It can be a 'rim brake rim' or a 'hub brake rim'.

What you do need is a different frame.
And then a disc hub, rotor, caliper, lever.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Tuesday, April 6, 2021 at 4:59:44 PM UTC-7, AMuzi wrote:
On 4/6/2021 5:59 PM, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

Doesn't matter.
It can be a 'rim brake rim' or a 'hub brake rim'.

What you do need is a different frame.
And then a disc hub, rotor, caliper, lever.

I think that long ago, before my concussion I converted a normal bike frame to hydraulic disks with those adaptors. And it worked though was pretty hopeless since disk frames have stronger stays and forks or they bend and cause changes in direction. About six years ago, I was visiting a frame builder in Phoenix and he said that he wouldn't build disk framesets because the loads were all contrary to frame integrity. My Felt shows that to be pretty much true since the stays and fork are massive.

AMuzi wrote:
On 4/6/2021 5:59 PM, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.


Doesn't matter.
It can be a 'rim brake rim' or a 'hub brake rim'.

What you do need is a different frame.
And then a disc hub, rotor, caliper, lever.


Some older 26in MTB did have mounts for both, ie V and disk brakes, though
admittedly not that many.

Roger Merriman.

On Tuesday, April 6, 2021 at 6:36:13 PM UTC-5, James wrote:
On 7/4/21 8:59 am, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

Practically any 26" MTB rim will do. The difference between rim brake
and disc brake specific rims is usually that the disc brake version
doesn't have a surface for rim brakes to work on - but it doesn't matter
if you use a rim designed for rim brakes on a wheel with a disc brake.
In fact you could use such a wheel in either rim or disc brake bikes!

Braking forces act from the hub through the spokes to the rim and tyre
with disc brakes. Make sure you have at least a 3x spoke lacing pattern.


How will you mount a disc brake calliper to what I presume is a rim
brake equipped bicycle frame?

--
JS
Not correct. I would needa rim with a spot to mount the disc for starters.

Andy

On 4/11/2021 4:14 PM, AK wrote:
On Tuesday, April 6, 2021 at 6:36:13 PM UTC-5, James wrote:
On 7/4/21 8:59 am, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

Practically any 26" MTB rim will do. The difference between rim brake
and disc brake specific rims is usually that the disc brake version
doesn't have a surface for rim brakes to work on - but it doesn't matter
if you use a rim designed for rim brakes on a wheel with a disc brake.
In fact you could use such a wheel in either rim or disc brake bikes!

Braking forces act from the hub through the spokes to the rim and tyre
with disc brakes. Make sure you have at least a 3x spoke lacing pattern.


How will you mount a disc brake calliper to what I presume is a rim
brake equipped bicycle frame?

--
JS
Not correct. I would needa rim with a spot to mount the disc for starters.

Andy


WTF?? That's nonsensical.

A disc brake grabs the _rotor_, not the rim. That's the
whole idea!

One may use thin laminated carbon fabric for a disc brake
rim which could not bear the heat of a rim brake.

But a chunk style XMart metal rim, made for rim brakes,
would function just as well if built into a disc brake wheel.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On 4/11/2021 2:14 PM, AK wrote:
On Tuesday, April 6, 2021 at 6:36:13 PM UTC-5, James wrote:
On 7/4/21 8:59 am, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

Practically any 26" MTB rim will do. The difference between rim brake
and disc brake specific rims is usually that the disc brake version
doesn't have a surface for rim brakes to work on - but it doesn't matter
if you use a rim designed for rim brakes on a wheel with a disc brake.
In fact you could use such a wheel in either rim or disc brake bikes!

Braking forces act from the hub through the spokes to the rim and tyre
with disc brakes. Make sure you have at least a 3x spoke lacing pattern.


How will you mount a disc brake calliper to what I presume is a rim
brake equipped bicycle frame?

--
JS
Not correct. I would needa rim with a spot to mount the disc for starters.

Andy

Are you confusing "rim" with "wheel"? Disc rotors mount to the hub, not
to the rim.

Mark J.

On Tuesday, April 6, 2021 at 6:59:02 PM UTC-4, AK wrote:
I have a 26 inch MTB.

I am thinking of converting the rear to disk brakes.

What kind of rim would I need?

Thanks.

A few years ago I bought an A2Z disc brake adapter

https://www.amazon.com/A2Z-Brake-Mou...ct_top?ie=UTF8

Amazon doesn't have them anymore, but I did see a few other on-line retailers (some of which seemed reputable).

It works ok, but I ran into two annoying issues:
- You have really clamp down the frame bolts, or the assembly will slide around. You learn the hard way to calibrate the brake with the assembly as far forward as possible, or aplying the brake forces the assembly forward and loosening the cable. Once that issue is squared away, Worst case is stopping on an uphill while using the rear brake to hold the bike. This forces the clamp away from the frame, pulling the cable tight and forcing the brake on to the effect that it locks the rear wheel without squeezing the lever. Once you really _really_ tighten the **** out of the frame bolts, it minimizes the problem.

- it only works with QR axles, (but if you have a bike with thru-axle or anything newer, you likely have disc mounting posts anyway) and you have to completely remove the QR skewer in order to get the rear wheel out.

Other than that it seems to work fine, definitely better than cantilevers. I have a beautiful Independent Fabrications Custom Deluxe Titanium 26" hardtail that rides like no other bike I've ever had. I couldn't bear to hang up the bike because of limited availability of higher-end rim brake wheels. I also have a C'Dale Habit 3 27.5. The rear braking is better on the C'dale mostly due to the fact that the C'dale has DEore XT hydraulics and I'm running Avid BB7 cables on the IF, but it's the rear brake, so adapting my riding style switching between the two has more to do with the shorter lighter IF hardtale versus the larger longer C'Dale FS than any issues with the rear braking modulation.