Disk Brakes and Dragging

My disk brakes are properly aligned and adjusted. Going up a mile long 10% grade today, whenever I swerved one way or the other, you could hear the disks screeching as the shoe would get thrown again the disk. The drag was quite apparent by the time I got to the top of that grade. I did this on the Colnago last week that has rim brakes and although the Redline is 5 lbs heavier by the time I hit the top of the grade it felt more like 10 lbs difference.

It is rather remarkable what the difference of only 5 lbs would make and I can only assume that the noise of the disk was indicating real dragging though I couldn't feel it, only heard it.

On 5/3/2020 5:38 PM, wrote:
My disk brakes are properly aligned and adjusted. Going up a mile long 10% grade today, whenever I swerved one way or the other, you could hear the disks screeching as the shoe would get thrown again the disk. The drag was quite apparent by the time I got to the top of that grade. I did this on the Colnago last week that has rim brakes and although the Redline is 5 lbs heavier by the time I hit the top of the grade it felt more like 10 lbs difference.

It is rather remarkable what the difference of only 5 lbs would make and I can only assume that the noise of the disk was indicating real dragging though I couldn't feel it, only heard it.


Could be frame flex. Or a loose hub bearing. Or a loose hub
QR. Shouldn't be all that hard to locate and rectify.

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

AMuzi wrote:
On 5/3/2020 5:38 PM, wrote:
My disk brakes are properly aligned and adjusted. Going up a mile long
10% grade today, whenever I swerved one way or the other, you could hear
the disks screeching as the shoe would get thrown again the disk. The
drag was quite apparent by the time I got to the top of that grade. I
did this on the Colnago last week that has rim brakes and although the
Redline is 5 lbs heavier by the time I hit the top of the grade it felt
more like 10 lbs difference.

It is rather remarkable what the difference of only 5 lbs would make and
I can only assume that the noise of the disk was indicating real
dragging though I couldn't feel it, only heard it.


Could be frame flex. Or a loose hub bearing. Or a loose hub
QR. Shouldn't be all that hard to locate and rectify.


Yup shouldn’t be that bad, sometimes get the odd zing off the commute bike,
but it’s not noticeably dragging just mildly annoying noises for a second
or so!

Roger Merriman

On 5/3/2020 7:44 PM, Roger Merriman wrote:
AMuzi wrote:
On 5/3/2020 5:38 PM, wrote:
My disk brakes are properly aligned and adjusted. Going up a mile long
10% grade today, whenever I swerved one way or the other, you could hear
the disks screeching as the shoe would get thrown again the disk. The
drag was quite apparent by the time I got to the top of that grade. I
did this on the Colnago last week that has rim brakes and although the
Redline is 5 lbs heavier by the time I hit the top of the grade it felt
more like 10 lbs difference.

It is rather remarkable what the difference of only 5 lbs would make and
I can only assume that the noise of the disk was indicating real
dragging though I couldn't feel it, only heard it.


Could be frame flex. Or a loose hub bearing. Or a loose hub
QR. Shouldn't be all that hard to locate and rectify.


Yup shouldn’t be that bad, sometimes get the odd zing off the commute bike,
but it’s not noticeably dragging just mildly annoying noises for a second
or so!

Shouldn't be hard to locate, but sometimes it is. Last year one of my
good riding friends bought his first disc brake bike at a local shop. He
(and we) heard odd and sporadic noises from the thing for weeks.
Climbing seemed to contribute. IIRC it took the shop at least three
tries to get it fixed.

I never heard exactly what the problem turned out to be.

I don't think he ever complained about feeling any drag, though. I think
it was just the annoyance of a noise that shouldn't be there.

--
- Frank Krygowski

Frank Krygowski wrote:
On 5/3/2020 7:44 PM, Roger Merriman wrote:
AMuzi wrote:
On 5/3/2020 5:38 PM, wrote:
My disk brakes are properly aligned and adjusted. Going up a mile long
10% grade today, whenever I swerved one way or the other, you could hear
the disks screeching as the shoe would get thrown again the disk. The
drag was quite apparent by the time I got to the top of that grade. I
did this on the Colnago last week that has rim brakes and although the
Redline is 5 lbs heavier by the time I hit the top of the grade it felt
more like 10 lbs difference.

It is rather remarkable what the difference of only 5 lbs would make and
I can only assume that the noise of the disk was indicating real
dragging though I couldn't feel it, only heard it.


Could be frame flex. Or a loose hub bearing. Or a loose hub
QR. Shouldn't be all that hard to locate and rectify.


Yup shouldn’t be that bad, sometimes get the odd zing off the commute bike,
but it’s not noticeably dragging just mildly annoying noises for a second
or so!

Shouldn't be hard to locate, but sometimes it is. Last year one of my
good riding friends bought his first disc brake bike at a local shop. He
(and we) heard odd and sporadic noises from the thing for weeks.
Climbing seemed to contribute. IIRC it took the shop at least three
tries to get it fixed.

I never heard exactly what the problem turned out to be.

I don't think he ever complained about feeling any drag, though. I think
it was just the annoyance of a noise that shouldn't be there.

My bikes are generally quiet I change pads as needed and I hose off
mud/dead sheep but beyond that leave them be!

In my experience folks who have trouble are fiddling, be that spraying with
various cleaners etc, and possibly compounded by dragging the brakes on
hills etc.

Disks generally like fair positive use, and to be largely left alone.

Roger Merriman