rotor warping on disc brakes

[cyberknight]

specifically single piston cable discs
Does anyone else suffer from this as my rotors are that warped i cannot get decent braking , the rear one was replaced about a year ago and its still rubbish .
Will upgrading to dual piston cable improve things ? changing to hydro is not an option .

 

[FishFright]

specifically single piston cable discs
Does anyone else suffer from this as my rotors are that warped i cannot get decent braking , the rear one was replaced about a year ago and its still rubbish .
Will upgrading to dual piston cable improve things ? changing to hydro is not an option .

Twin piston brakes work much better and don't mess up rotors in the same way.

 

[rogerzilla]

If the caliper is floating (as on cars, except high performance models) it shouldn't matter. The cheaper bicycle brakes rely on the disc bending, though.

 

[Drago]

Never had a problem and being a big fat fecker large muscular chap my brakes have their work cut out.

Not saying it is the cas here, but too may cyclists don't know how to brake properly, comfort brake all over the place, and get the heating-cooling cycles just wrong and you have the conditions for disc warping.

 

[fritz katzenjammer]

I mistake I see on these brakes is that some shops set the calliper up so they are cantered over the rotor like you would with a twin piston hydraulic unit, this requires that the rotor flexes a lot more during use. Set them up so the static pad is as close as possible to the rotor without rubbing, either by manually adjusting the static pad inward or by offsetting the calliper, this reduces flexing of the rotor and assures a decent amount of braking power as the pads will now hit the rotor more squarely. You have to start with a straight rotor though, I often spend more time messing with rotor runout than setting up the calliper son most new bikes.

Given how well a decent set of rim brakes work I often wonder why people bother with discs for casual cycling.

 

[Drago]

Given how well a decent set of rim brakes work I often wonder why people bother with discs for casual cycycling.

Good heqvens above, that's torn it!

 

[Joffey]

Had a bit of an issue with this recently. Bought a tool and straightened them again. All seems to be fine now.

 

[Joffey]

Given how well a decent set of rim brakes work I often wonder why people bother with discs for casual cycling.

Cos I’m fat and ride down big hills… rims don’t stop me!

 

[Drago]

I guarantee I'm fatter and they stop me.

 

[cyberknight]

I mistake I see on these brakes is that some shops set the calliper up so they are cantered over the rotor like you would with a twin piston hydraulic unit, this requires that the rotor flexes a lot more during use. Set them up so the static pad is as close as possible to the rotor without rubbing, either by manually adjusting the static pad inward or by offsetting the calliper, this reduces flexing of the rotor and assures a decent amount of braking power as the pads will now hit the rotor more squarely. You have to start with a straight rotor though, I often spend more time messing with rotor runout than setting up the calliper son most new bikes.

Given how well a decent set of rim brakes work I often wonder why people bother with discs for casual cycling.

it was set up right but as time has gone on they have just got worse , this is on the all weather commuter so disc when working properly are better when descending when its piddling it down

 

[fritz katzenjammer]

Good heqvens above, that's torn it!

Heresy I know…

I also prefer Suntour Cyclone over Campagnolo Nuevo Record.

Obviously barking mad.

 

[fritz katzenjammer]

it was set up right but as time has gone on they have just got worse , this is on the all weather commuter so disc when working properly are better when descending when its piddling it down

With a single sided caliper you need to be adjusting the static pad inward as it wears to maintain good brake performance. There should be an adjuster on the side of the calliper where you can insert a hex key and adjust the pad. You may have to remove the rear wheel to do that end of the bike which makes it a bit of a trial and error process. Just another piece of poor modern bike design that I love.

Don’t get me started on carbon frames.

 

[fritz katzenjammer]

Cos I’m fat and ride down big hills… rims don’t stop me!

I guarantee I'm fatter and they stop me.

I’ve possibly got you both beat… Frau Fritz and I run a tandem so I’m piloting a 40 pound bicycle with an extra human on the back and the old rim brakes work really very well.

 

[Joffey]

I’ve possibly got you both beat… Frau Fritz and I run a tandem so I’m piloting a 40 pound bicycle with an extra human on the back and the old rim brakes work really very well.

You go 40mph down hill on a tandem?? You are pretty brave!!

 

[Drago]

They work fine for me because I know how to beake properly and how to set them up.

However, discs do undeniably bring advantages in certain respects and mentioning rim brakes on a disc brake topic has been known to go as far as people getting stabbed. Accy got 18 months in the scrubs for one rim brake related beating when he filled a fedora with bricks and used it to beat a disc brake fan half to death.