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Hi Guys.

I put bigger brakes on my red stag a few month ago, brand new pads, rotors re-done .

Since then, my brakes shake very much when i brake slowly, when i brake hard, everything is okay, why.!

Edited by Stagea Denmark
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https://www.sau.com.au/forums/topic/219413-r33-brake-upgrade-and-problems/
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fitting 'bigger' brakes will do that, your ABS kicks in sooner. Can test by pulling the fuse on ABS, will confirm it's your abs and not a warped disc etc.

Thanks, if i remove the fuse to the ABS, will it then stop shaking, just a little test.!!

if it was your ABS, it would be getting worse under heavy braking, not better.

could be either warped rotors, badly bedded in pads or a loose wheel bearing.

This is assuming, of course, that you have had your wheels rebalanced....

if it was your ABS, it would be getting worse under heavy braking, not better.

could be either warped rotors, badly bedded in pads or a loose wheel bearing.

This is assuming, of course, that you have had your wheels rebalanced....

There is no problems under heavy braking, only when i brake normally.

Alle wheels are rebalanced, one of my friend told me to get the front-wheels rebalanced, when the wheels is on the car, maybe it cut be the aksels.!

Are your rotors slotted?

It MAY be pad knock off. There is no chance that you have put the pads in back to front?

(It is possible to do this, especially if the left hand pads are on the right hand side of the car and vice versa)

I doubt it would be the axles, the vibration would be evident in acceleration, plus it would only be apparent when the ATESSA kicks in.

Are your rotors slotted?

It MAY be pad knock off. There is no chance that you have put the pads in back to front?

(It is possible to do this, especially if the left hand pads are on the right hand side of the car and vice versa)

I doubt it would be the axles, the vibration would be evident in acceleration, plus it would only be apparent when the ATESSA kicks in.

No, it is standard slots.

I didn't know it was possible to attach pads 180°, i will take a look today, thanks m8.

How can i see, that the pads is sitting in the right possision.!

Edited by Stagea Denmark
sounds funny, but is the caliper bolted on tightly? does it use caliper adapters of some sort (and if so is it tight too?). And finally, is the disc centred correctly in the caliper?

Really, i have no idea, i hope everything is centred, but this is stange, i will attach some pictures of what i have mounted.

post-46420-1210956467_thumb.jpg

post-46420-1210956499_thumb.jpg

post-46420-1210956540_thumb.jpg

fitting 'bigger' brakes will do that, your ABS kicks in sooner. Can test by pulling the fuse on ABS, will confirm it's your abs and not a warped disc etc.

..... ummmm ok :)

did u bed the new pads in on the rotor face or just ive them a smashing, which would cause warping??? even if new.

..... ummmm ok :)

did u bed the new pads in on the rotor face or just ive them a smashing, which would cause warping??? even if new.

Didn't understand that, but there is (Not sure this is the right word) Cobber-grease on the pads.

What he is saying, is when you put new pads on, and this is even more important with new rotors and new pads, is you need to avoid all heavy braking when the pads are new (say, the first 500kms)

This can cause the rotors ro warp. Another thing you need to avoid, is sitting at traffic lights (or wherever) with your foot hard on the brakes as this will do the same thing.

OK, now to diagnose the problem. With the wheel off, give the brake disc a good hard shake by hand. Can you feel/hear any clunking or knocking? This would indicate something is loose - such as a wheel bearing or disc mount. If you can't hear or feel anything, you need to mount a dial indicator up and check the runout on the disc. This will tell you weather or not you have a warped rotor. If you don't get any joy from either of these 2 tests then it is time to look VERY closely at your caliper mounts.

Can anyone else add to this?

What he is saying, is when you put new pads on, and this is even more important with new rotors and new pads, is you need to avoid all heavy braking when the pads are new (say, the first 500kms)

This can cause the rotors ro warp. Another thing you need to avoid, is sitting at traffic lights (or wherever) with your foot hard on the brakes as this will do the same thing.

OK, now to diagnose the problem. With the wheel off, give the brake disc a good hard shake by hand. Can you feel/hear any clunking or knocking? This would indicate something is loose - such as a wheel bearing or disc mount. If you can't hear or feel anything, you need to mount a dial indicator up and check the runout on the disc. This will tell you weather or not you have a warped rotor. If you don't get any joy from either of these 2 tests then it is time to look VERY closely at your caliper mounts.

Can anyone else add to this?

well bedding the the brakes are quite easy, 4or 5 relativelly hard stops from 80-90 kph down to 30kph to remove surface rubish off the pads which allows the disc to warm up and pads bed in, then leave brakes to cool down. process finished. also put a dial indicator on the disc surface and check runout , dont want any more than 3-4 thou . If it is the discs you will have a slight jerkiness (hesitation) when rolling with your foot slightly on the pedal. Hope this helpes

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