so i've managed to warp 2 sets of discs on my focus since i bought it 3 years ago. its an 1800 03 plate, the guy i bought it off had put 300mm discs and calipers off an st170 on it, and i can understand those being cheap as he was repairing it to sell (was a cat d write off), the second lot came from a tyres place and despite the price they were obviously cheap crap aswell.

so i need ur advice, as my old mans going away this weekend i thought i'd take the opportunity to change the discs on his nice flat drive, and bleed the whole system.

i've seen these which seem a decent price,

http://www.motorsportworld.co.uk/framefix.asp?productcode=KBD1214G&PID=44174

any thoughts on the brand to buy.

also a thought was the brake bias may be wrong now, and perhaps the drums want adjusting as per advice on here, also the abs has been disabled, and i may drive on occasion, spiritedly...

I had black diamond drilled and grooved discs with the black diamond pads on my old SAAB 900 (vectra). They were the best brakes I've had on any car I've owned. Probably helped by the braided lines too.

All in all a bargain for £50 off the 'bay

Fancy brake discs are snake oil.
Check the calipers are free and fluid is flowing easily back to master cylinder. If any doubt about the calipers being free fit new seals and flex hoses

Clean the mating surfaces of disc and hub before fitting.

Don't over fill the fluid resevoir -- leave room for fluid expansion.

The rest is purely down to driving habits, don't hold the car on the foot brake at traffic lights when the brakes are stonking hot.

When the brakes are hot drive the car more gently for a mile or two before parking up.

Finally don't drag the brakes into corners.





[Edited on 15/9/10 by britishtrident]

urban myth........

I also warped my 300mm setup quite easy I would try a set of genuine disks on there if there not allready

The main cause is when the brakes are hot when the car is stationary the pad and the area of disc under the caliper cools much slower than the rest of the disc which is exposed to cool ambient air.

As a result internal stresses are generated within the disc due differential contraction.

quote:

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Originally posted by clairetoo
urban myth........

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As said, make sure the hub flanges are totaly clear of rust. I always smear it with copperslip and then wipe it off, leaving just a residue behind. Not had a set of discs I've fitted come back again for as long as I can remember... and I've lost count long ago of how many I've fitter.

On a road car drilled, grooved, etc is snake oil. TRW and Apec discs are my choice, cost/quality wise. Buy cheap stuff and you'll get what you pay for and beware of counterfeits. Discs are relativly cheap anyway.

adrian

well the font of all knowledge does me proud again.

thanks all, and i've gone for apec stuff btw adrian, £70odd inc vat for discs and pads.

quote:

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On a road car drilled, grooved, etc is snake oil

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Warping is a myth. Dont park with them hot and apply the brakes and they're normally fine.

Ive had allsorts, drilled ones crack, grooved wear faster, normal plain disks have never caused me a major issue and at less than £50 a set theyre hardly dear