Groovy Discs?

[Guest smokinslim]

How long on average should grooved brake disks remain grooved, i mean i expect they wear away eventually but should have a reasonable lifespan.

The reason i ask is i bought and fitted a pair on the front of me car last summer. Whilst stripping the front end end yesterday i discovered that the grooves have practically gone from the discs, they seem more etched than grooved now When i first noticed it, i checked the pads on that disc. They were pretty worn but not down to metal. Checked the other side which i know has an iffy caliper, the pads were hardly worn since the discs went on, but the disc was just the same as the other side.

The bloke i got them from will be hearing from me shortly but i want to gather a few opinions on this first.

[Jonmurgie 2]

What make discs are they? I'd have said that if the grooves have gone the discs will need replacing... is there much of a lip on the outer edge of the disc?

[hengti 2]

What make discs are they? I'd have said that if the grooves have gone the discs will need replacing... is there much of a lip on the outer edge of the disc?

 

 

i'd second that

 

mine's got tarox drilled/grooved discs - the grooves are quite deep on tarox discs, but they're still very prominent after 60k miles

 

the grooves on ebc/mintex discs (for eg) are much shallower

[Guest smokinslim]

I found them on ebay (i know...), supposed to be the same as red dot but came in a plain box with no labels, instructions etc.

The grooves were 2-3mm deep at least, will check later. The only apparent lip is towards the centre of the discs were the pads don't touch. Don't think i've done more than 10k sinces they've been on. Gonna measure the thickness of the disc as the original discs are still good, will have to swap them back if they're too thin.

I don't understand why the grooves have gone on both sides when only one calipers working fully though, very strange.

[C_W 3 1 Cars]

I can't seem them being 3 mm deep, usually they'd be about 1 or 1.5mm deep. If the grooves have gone and they really were 3mm deep then you'd lose 6mm from the width of the disc which would mean they'd be very very thin now.

 

Manfucaturers usually give a minimum thickness of about 2mm thinner than new thickness.

[Guest smokinslim]

You're closer to the mark there C_W, 2-3mm was off the top of my head when i'd jus woke up. Either way there's bugger all left of them.

Checked the thickness of the discs this afternoon, both are 10mm. If they wear any more i'll have to swap back to be on the safe side.

I plan to change to 307 setup when i have the money spare but that probably wont be for a few months yet.

 

Something that crossed my mind as possibly what has happened here is that the bloke who kindly ( ) sold me the discs, has been buying numbers and getting his groove on if u get what i mean. Buying cheapo discs and cutting grooves into them himself.

What affect would this have on the longevity of the discs?

 

The other thing is, how much difference does it make which way the grooves face? Got a different answer each time i asked someone before fitting them and hadn't discovered this forum at that time.

I'm currently on ferrodo pads by the way, the previous discs seemed to be fine with them; just generally pants.

[C_W 3 1 Cars]

10mm? They must be solid front discs?

 

I've read different views on the way the grooves should face but I don't think it makes a difference as they aren't really there for directing air, but allowing gas to escape or pad deglazing.

[Rippthrough 98]

10mm? They must be solid front discs?

 

I've read different views on the way the grooves should face but I don't think it makes a difference as they aren't really there for directing air, but allowing gas to escape or pad deglazing.

 

 

Aren't the OEM solids 10mm anyway?

Some of the aftermarket use 12 though.

[Wes 86 1 Cars]

if they are 6 groove they should go against the wheel direction, if they are 20 or 40 groove they should go with the direction of the wheel if that makes sense. it should tell you that in the instructions though.

[Guest smokinslim]

Just been taking some pics of my calipers for someone so thought i'd update this thread with some pics of whats goin on : front, rear

 

I took a pic that was mainly the disc buteven though it uploaded fine from the camera and was clearly visible in the filing system, it's invisible in my photosoftware and photobucket alike.

[C_W 3 1 Cars]

Yea they look like solid discs so will be about 10mm but not sure what original thickness of those discs are but can't imagine what they'd be like at less than 10mm thick when I'm used to 26mm thick discs causing me problems!

[Guest smokinslim]

I know for a fact that they are solid discs as i put them there, recommendation is to change discs that are thinner than 9mm. I'm not to concerned about that as i still have my previous discs, which are still in good condition but aren't grooved. I'm merely trying to find out why the grooves may have worn away so quickly on the discs i'm using at the moment. Brand new in july and nearly f**ked already???

[Rippthrough 98]

I know for a fact that they are solid discs as i put them there, recommendation is to change discs that are thinner than 9mm. I'm not to concerned about that as i still have my previous discs, which are still in good condition but aren't grooved. I'm merely trying to find out why the grooves may have worn away so quickly on the discs i'm using at the moment. Brand new in july and nearly f**ked already???

 

 

Sure they've worn and it's not just that the edges ave been rounded by the pads?

That would make them much less defined, so they'd look like they had worn a lot.

[hengti 2]

I'd just bin them mate

 

apart from the fact that they appear to have worn badly, they also look quite badly corroded for 8 months old! just crappy quality i guess

 

did they perform any better than the std ones you took off? stick the std ones back on if not

or canvass for people's opinions about what you should replace them with

[Rippthrough 98]

I'd just bin them mate

 

apart from the fact that they appear to have worn badly, they also look quite badly corroded for 8 months old! just crappy quality i guess

 

did they perform any better than the std ones you took off? stick the std ones back on if not

or canvass for people's opinions about what you should replace them with

 

GSF's Brembo OEM's. Take forever to wear down.

 

Or use it as an excuse to upgrade to 266mm. Those Bendix calipers kinda suck.

[Guest smokinslim]

Most of the corrosion is due to the car having been off the road for the past couple of weeks (replaced clutch release bearing and peugeot cant get me the correct clutch cable to put everything back together), however the grooves are much less aparrent than they were when i got them hence this topic. The discs do, even in their current state, give a noticable improvement to braking - with a quite a distinctive noise too.

I've experienced black diamond discs and pads on a similar brake setup to mine, and they worked well - but were something like £150, my discs were about £35. The only reason i got them as i wasn't looking at the time.