Braking problem at high speed

[Eros]

In my 2003 clio sport, I have this problem: When I brake hard (but not enough for de ABS to activate) at high speed (around 200 km/h) the car starts to get sideways and I have to countersteer to compensate.
At low speeds (60 km/h) the car brakes perfectly straight.

The problem it´s supposed to be on the rear brakes but I took the car to the mecanic, a guy who is a specialist on suspension and brakes and he couldn´t find anything wrong. The only thing he could come up with is that the pads are kinda worn, but no so much.

Any ideas ?

 

[Fred@BTM]

how sideways?

what tyre pressures?
is the wheel alingment ok?
do you have a faulty front caliper (common)

 

[Eros]

Sideways : it TENDS to go sideways but I countersteer to compensate. If I don´t compensate I probably go on a spin.

The tire pressures: are I´m sure the are OK, I always check them.

The front calipers: I got changed the front pads recently and the front calipers seemed OK. (the rear calipers seemed ok too.)

The wheel alignment I guess it´s ok. When I´m not breaking at high speeds evrything it´s 100% normal.

 

[dick]

could it not be one of the rear brakes?

had a similar thing in mine, one side was on more than the other and was doing same thing, when braking hard, but not noticable when not really qwuick

 

[S22 JGS]

200kmh - thats like 140mph+ isnt it.... gotta be a dick to drive at that speed anyway

 

[Johnc172]

I get this in my cup when doing track days, coming down a long straight and slam the brakes ready for the corner, the back gets all twichy, i've just put it down to it being light at the back (as its stripped out) and good brakes at the front!!

 

[Eros]

200kmh - thats like 140mph+ isnt it.... gotta be a dick to drive at that speed anyway

Why would you get a clio sport if you don´t want to go fast ?

 

[Rob669]

That's silly M8. The car is on its limits, therefore what do you expect.

I agree though, that's what the car's for.

Cheers, Rob669

 

[MrMark]

200kmh - thats like 140mph+ isnt it.... gotta be a dick to drive at that speed anyway

Why would you get a clio sport if you don´t want to go fast ?

because its dangerous to you and other road users.


If you have a bugatti (sp?), you dont drive at 200mph, just cause you got one.

 

[Eros]

The ABS system and the traction control and all that stuff isn´t supposed to prevent the the back getting "all twichy"?

 

[GordonD]

In my 2003 clio sport, I have this problem: When I brake hard (but not enough for de ABS to activate) at high speed (around 200 km/h) the car starts to get sideways and I have to countersteer to compensate.
At low speeds (60 km/h) the car brakes perfectly straight.

The problem it´s supposed to be on the rear brakes but I took the car to the mecanic, a guy who is a specialist on suspension and brakes and he couldn´t find anything wrong. The only thing he could come up with is that the pads are kinda worn, but no so much.

Any ideas ?

My idea is that its not in the rear brakes its in the front ones.

I'd wonder if it wasn't something to do with the fact that you worked on them recently. I have no idea of your competence and carefulness, but if I did something, then a problem occurred, the first question I'd ask myself is whether I'd done it right.

Even aside from that, given that the front brakes are doing most of the work and are attached to steered wheels, that's where I'd look if I had to countersteer to keep the car braking in a straight line. Especially on a front-wheel-drive car where the back end does bugger-all more than keep the cars arse from dragging on the ground. You can have a flat rear tyre on a Clio and not notice.

 

[bigmonmulgrew]

You got electronic brake distribution. Maybe its not happy at 140 so its applying less force to one wheel trying to keep traction but getting it wrong

 

[marko_498]

200kmh - thats like 140mph+ isnt it.... gotta be a dick to drive at that speed anyway

(No1) 200 kmh is 124 mph not 140+ :rasp:

(No2) its most likely like has been mentioned that more force is being applied to one side due to uneven wear. Tray getting the mechanic u had to come out in the car with you

 

[Eros]

GordonD :"I'd wonder if it wasn't something to do with the fact that you worked on them recently."

I had the problem before and after I changed the front pads.

marko_498: "its most likely like has been mentioned that more force is being applied to one side due to uneven wear"

The rear pads are worn evenly and the disks are great (no trenches no nothing).

The fornt disks are good and the front pads are new.