Riders on disc brakes. How often do you lock up your rear wheel?

Discuss light weight issues concerning road bikes & parts.
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Shrike
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by Shrike

Be honest.

Have a reason for asking and it's not to start a rim v DB flame war (again).

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themidge
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by themidge

Shrike wrote:
Sat May 26, 2018 3:59 pm
it's not to start a rim v DB flame war (again).
:doh:

by Weenie


scale29
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by scale29

Honestly, never. I have brake levers operated by fingers, not on/off switches. I have the ability to moderate my braking force.

Maybe it helps having raced MTB and Cross with a crit racing for years and I ride a non ABS motorcycle? or maybe I just understand how brakes work??

Shrike
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by Shrike

What about really tight situations and you need to brake super hard. Would you say DBs
locking up the rear wheel is more or less likely than rim brakes?

scale29
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by scale29

No more, no less. I can easily lock a rear caliper brake if I haul on the lever, same on a disc, if anything less likely as you can feel the modulation and apply/decrease brake pressure as required.

Ginsterdrz
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by Ginsterdrz

Nope. Never locked the rear. I’m sure if I was really crass or reckless I could.
Maybe MTB gives you better control and intuitive weight distribution as scale29 says.

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Miller
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by Miller

Got my new Campag Potenza disc brakes in operation and am loving them, they're the best brakes I've ever used. I should qualify that by adding I have not been in the habit of crashing due to brake deficiency, I have a bike with perfectly effective rim brakes, but the disc brakes give you a feeling of having masses of controllable stopping power. The modulation is excellent. You can lock the back wheel if you choose to but it's not something that should happen unless you panic.

TobinHatesYou
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by TobinHatesYou

Shrike wrote:
Sat May 26, 2018 3:59 pm
Be honest.

Have a reason for asking and it's not to start a rim v DB flame war (again).

Never. The only time I "lock up" the rear is in the final milliseconds of a complete stop if I'm feeling lazy. And that's partly because I'm already out of the saddle with one foot unclipped, so my weight is shifted forward.

If you have a problem with locking up your rear with any kind of brake, I suggest you learn how to ride a bike.
Last edited by TobinHatesYou on Sat May 26, 2018 9:28 pm, edited 1 time in total.

RyanH
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by RyanH

My brief time on disc I found it a lot harder to lock up the rear in an all out stop than rim brakes. It's mechanical leverage. Rim brakes are a lot further from the axis so they can theoretically apply more force at the expense of modulation which means toeing the line of locking the rear and not has a much smaller margin of error.

Edited to add: every time I went back to my rim brakes bike, I had to adjust how I brakes because I kept locking the rear if I tried to brake like I did on disc.

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TonyM
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by TonyM

Never happened so far.

Squashednuts
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by Squashednuts

Once when I've been riding in the city and a car did something unexpected....
I know...when you least expect it, expect it

I've applied brakes full force & locked rear...then fleeting panic...then phew

For sake of context, I've done about 15k km with plenty of hills

TobinHatesYou
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by TobinHatesYou

To clarify: (worse) modulation is why it's more likely to lock a rim-brake. Disc-brakes have as much or more actual brake force/power because what is lost in mechanical advantage is gained in friction force (pad rigidity/hardness, brake surface rigidity/hardness, clamping pressure.)

dcorn
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by dcorn

In the couple months I've been on road disc, I've done it a few times. It's been stops from pretty high speed at the bottom of a descent where I thought I'd have more time to slow down. Like when I'm going to roll through a yield behind a car, but then the car stops unexpectedly.

Honestly though, a real wheel skid is super easy to control, even when unexpected. Been practicing since I was a kid on friction brakes lol.

Shrike
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by Shrike

RyanH wrote:
Sat May 26, 2018 8:48 pm
My brief time on disc I found it a lot harder to lock up the rear in an all out stop than rim brakes. It's mechanical leverage. Rim brakes are a lot further from the axis so they can theoretically apply more force at the expense of modulation which means toeing the line of locking the rear and not has a much smaller margin of error.

Edited to add: every time I went back to my rim brakes bike, I had to adjust how I brakes because I kept locking the rear if I tried to brake like I did on disc.
Brill thanks Ryan, that's what I was looking for. They're quite different systems so you'd imagine one would be easier to lock out than the other.

Been experimenting with my wheelsets this weekend and was quite surprised by how easy/hard some pad/wheel combinations are to lock out if you sprint into an emergency stop. Got me thinking about discs. Are they mechanically harder to lock out or does it more depend on the materials used. Guessing a bit of both.

zmjones
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by zmjones

during a panic stop on occasion, but otherwise never.

by Weenie


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