Brake imbalance

[Mike Scib]

Right tonight's question

On my VX220 the front left brake is locking up! Pistons are free and the pins are clean, plus no brake drag after coming off the brakes.

Any ideas?

Also, CL brake pads, acceptable?

[robin]

What do the disks look like? That pad looks a bit suspect - as though it might only be working on the trailing edge? Don't understand why that would be ... unless the caliper is wonky?!

Have you done anything to the suspension (assume yes, given thread about bolts). Is it possible the corner weights are miles out (i.e. not much weight on front left)? Is it possible you have much less damping on the front left than the other corners?

[Mike Scib]

What do the disks look like? That pad looks a bit suspect - as though it might only be working on the trailing edge? Don't understand why that would be ... unless the caliper is wonky?!

Have you done anything to the suspension (assume yes, given thread about bolts). Is it possible the corner weights are miles out (i.e. not much weight on front left)? Is it possible you have much less damping on the front left than the other corners?

Discs were a little tired, drilled and grooved but have now been changed for blank Brembo's.

Seems that it was common at one point. Not sure how old the pads are as they came on the car;
http://arc.seloc.org/viewthread.php?tid=334404

Just fitted new Gaz coilovers (replaced under warranty) and set up the ride heights today and set up the rebound the same all round, it was also doing it with the old Bilsteins on. Had a pax in the car today, just the same as you said I thought it was corner weights.

[woody]

Mike, remember my car always used to lock the front right. Callipers changed, rear callipers changed, master cylinder changed, ride heights checked, geo checked , all had no effect. Then I changed the front bushes. The difference is night & day. Not sure if you're doing that anyway with the suspension bike change? There was no play or signs of wear in the bushes before I changed them.

[Mike Scib]

Mike, remember my car always used to lock the front right. Callipers changed, rear callipers changed, master cylinder changed, ride heights checked, geo checked , all had no effect. Then I changed the front bushes. The difference is night & day. Not sure if you're doing that anyway with the suspension bike change? There was no play or signs of wear in the bushes before I changed them.

I did wonder about the bushes in the front upper wishbone as you can move it from front to back with a pry bar, both sides. Also wondered about the geo but it would have to be a fair bit out I would imagine

Mate has a MOT station with a brake tester so hope to get onto that on Monday so long as the car is not too low! Least that way I can narrow it down to the brakes or something else!

Mike (loves cars! )

[David]

IMHO the pitting on the pad suggests it has been used hard after being contaminated with (most likely) moisture. Are the pads old and has the car sat for a long time with out use, have the wheels have been frequently washed, etc, etc? New pads anyway.

[Scuffers]

IHMO, don't use CL pads....

this is just another example of the ever expanding issue list.

[Mike Scib]

Pads are an easy fix then.

What about the brake imbalance??

[roadboy]

IHMO, don't use CL pads....

this is just another example of the ever expanding issue list.

What he said! I won't touch them. Seen far too many fall apart and never ever seen that with Pagid pads.

Dan

[tut]

Snap, tried Cl 6's once which wrecked my disks, then went onto Cl5's and at Spazz one rear pad was ripped off the backing plate.

Back onto Pagid 14's.

tut

[pete]

I had CLs fail at Spa too. Spoke to EP about it and I wasn't the first.

[Mike Scib]

Well that will be my first job tomorrow, stick the DS2500 back in!

Hopefully I will have some answers once I have been on the brake tester tomorrow about the brake imbalance.

Could it be the pads!!??

[BigD]

I think that's what's been suggested. Easiest thing to try though.

[Mike Scib]

Well pads changed, and I took it out for a little run to bed the brakes in and 'think' it may well be better, was to damp to really tell.

Did think I found the problem at one point as noticed what I thought to be no caster shims on the rear of the front upper wishbone, but it turns out it does have the small ones fitted (number 28)

https://www.deroure.com/diagrams.asp?TB ... 0035F&SC=1

[Mike Scib]

Well looks like the pads may have fixed the problem after all now that they have been properly bedded in! Now running DS2500's.

The brake tester also weighs the car, not sure how accurate it is but 780kg with an empty tank of fuel. What does a Elise/Exige SC weigh roughly?

Mike