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Wobba
07-02-2009, 22:23
Ok, my car is lowered on coilovers and I recently changed my front discs and pads, and the pads on the rear.

The rear pads were very worn, the fronts, not much wear at all.

Now, all dandy you think...oh, no, this is a CLIO, and is thus cursed.

So, there's me after redoing all my suspension and my brakes, all seems ok...but wait, whats this? When I brake hard it feels like the rears are locking up, and pulling to the right. You see the front of the car dip down under braking and the nose suddenly pointing right. It's not fun in fast corners I tell you!

Today, I refitted my AVO's for the third time in as many weeks (as they broke as well, twice), and removed my aux tank and replaced that too. I assumed it was a caliper on the right locking up, pulling the car right. I took it all apart, made sure the piston was all groovy and reset the pads and ensured the little notch on the back of the pad was in the piston properly. Put it all back together. It's still the same.

Now, it COULD be my bias valve needs adjusting but I don't know if I should tighten, or slacken the lock nut and main nut at the end. I also don't know how seized it is. It feels stiff but moveable. There seems some slack in it tbh.

Now, tomorrow morning I will jack the rear up and have a look at the other caliper on the rear nearside. Is there anything it could obviously be other than this, and which way do I adjust the bias valve for a lowered car?

stevie_b
08-02-2009, 09:35
More than likely it is the bias valve, unless you are only ever locking up on the one side? If you have lowered the car then it will think there is more weight on the rear axle than there really is. I've junked my standard bias control thing but from memory you should just loosen the nut so that the rod only comes under tension when the car is under more load at the rear.

Wobba
16-02-2009, 09:44
Ok, update. I bled my brakes on Saturday. A lot of air came out of the rear offside, and I have a feeling there could be more.

The brakes are a lot better, but still pull under braking.

I'll adjust the bias valve a bit, and re-bleed a bit, but if it's not that then what else?

Master cylinder seals?

MOT is now tomorrow morning...

stevie_b
16-02-2009, 10:05
Bleed it with plenty of weight in the rear ideally, and the rear beam under load, rather than jacking the car up and sitting it on axle stands on the jacking points as that will result in zero load on the axle and the bias valve will shut off more.

Wobba
16-02-2009, 10:27
Bleed it with plenty of weight in the rear ideally, and the rear beam under load, rather than jacking the car up and sitting it on axle stands on the jacking points as that will result in zero load on the axle and the bias valve will shut off more.

Pain to do on a lowered car :D

I could just have one wheel on ground and jack the side to bleed up a bit.

Wobba
16-02-2009, 11:37
On the brake bias valve, am I right in thinking it is just the two nuts at the end of the bar that holds the bias valve pivot arm in place that I need to adjust?

Gonna add a bit of length to it to compensate for the lowered rear.

If that's it then it's easy.