Wierd breaking at very low speed

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Scottd
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Wierd breaking at very low speed

Post by Scottd » Fri Jun 23, 2006 1:19 pm

As I'm breaking to about 10-5mph, I feel the car speed up, slow down, speed up, sort of pulsing, it's hardly noticable at all (passengers can't tell)... but I notice it. There's nothing strange about the feel from the pedal but can tell the car's not coming to a stop correctly.
Fairly new pads and discs but it is time to change the brake fluid, could it be that? :?

cheers

scott

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Shug
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Post by Shug » Fri Jun 23, 2006 1:21 pm

If it's really low (like walking) pace, maybe uneven build up on the discs? Can't see how fluid would make it pulse...

If so, try re-bedding. If that doesn't sort it, get the discs skimmed.
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Tom
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Re: Wierd breaking at very low speed

Post by Tom » Fri Jun 23, 2006 1:25 pm

Scottd wrote:As I'm breaking to about 10-5mph, I feel the car speed up, slow down, speed up, sort of pulsing, it's hardly noticable at all (passengers can't tell)... but I notice it. There's nothing strange about the feel from the pedal but can tell the car's not coming to a stop correctly.
Fairly new pads and discs but it is time to change the brake fluid, could it be that? :?

cheers

scott
I've got exactly that as well scott. newish disks and pads, but car had a soft life before me. will try bedding properly. Let me know how you get on. :D
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Scottd
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Post by Scottd » Fri Jun 23, 2006 1:27 pm

Yea, it's at walking pace, so slower than I said really. An uneven build up? of what? :)
I'm not sure if it does it all the time either, I'll keep an eye on it.

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Shug
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Post by Shug » Fri Jun 23, 2006 1:30 pm

When you bed pads in, what you are doing is transferring pad material into the structure of the disc. If it's not done right, or the discs are overheated and sat with the pads on them, the build-up is uneven and can cause what most people will call a warped disc.
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Stephen
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Post by Stephen » Fri Jun 23, 2006 4:11 pm

Have your brakes ever bound on or do you have a pad shaped mark on your disk?
This often happens causing a wee rusty bit that would give the feeling that you describe. As the disk rotates and the pads rub on a rusty bit then smooth bit etc
If you're not living on the edge you're wasting too much space!

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Scottd
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Post by Scottd » Fri Jun 23, 2006 4:29 pm

I'll take a better look at them later tonight.

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Post by tenkfeet » Sat Jun 24, 2006 6:22 am


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Uldis
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Post by Uldis » Sat Jun 24, 2006 8:15 am

Uneven pad build up or in new disks could be just the manufactuing tolerance.
Whatever the cause, you have a varying disk thickness so for the same pedal travel you have a place with more pad pressure and a place with less.

Apartfrom skimming, nothing you can do, and unless it's very bad it's not worth it.
DIY recipy to wear out the thick spots: a healthy track sesson :D

If that doesn't do it, then another one :D :D

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Lawrence
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Post by Lawrence » Sat Jun 24, 2006 10:04 am

tenkfeet wrote:Interesting reading

http://www.stoptech.com/tech_info/wp_wa ... disk.shtml#
Some very intresting reading here especially this which may be tut's problem

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Stephen
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Post by Stephen » Sat Jun 24, 2006 10:58 am

lawrence,
that should'nt be a problem with MMC's though should it?
If you're not living on the edge you're wasting too much space!

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Post by Lawrence » Sat Jun 24, 2006 11:25 am

Stephen wrote:lawrence,
that should'nt be a problem with MMC's though should it?
<Sherlock_Holmes> We must fall back upon the old axiom that when all other contingencies fail, whatever remains, however improbable, must be the truth.</Sherlock_Holmes>


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