LCR Brake Disc Skimming, Sizes & Options

[CBass]

I have just had the 40k service completed for my LCR and the SEAT Dealer told me that my front pads will need replacing in about 4k miles and that the discs will need skimming to remove the lip that has appear around the edge to stop the new pads sitting on top of the lip rather than flush with the discs.

I have heard that the minimum thickness for LCR discs is 26mm and that the discs are only 28mm to start with so shouldn’t be skimmed. Does anyone have and ideas / views on this? The size of the lip is no more than 1mm, it certainly isn’t thicker than a 10p coin, which I seem to remember is another way to judge it…

If I do need new disc too, am right that the front size is 323mm x 28mm and the rear size is 256mm x 22mm? (I think that is right from searching!)

Looking at either getting some grooved ones from Bill at Badger5 or drilled/grooved ones from The TT Shop (http://www.thettshop.com) in Bedford. I have read all the views on drilling discs making them liable to cracking in extreme track conditions, but as I don’t do this, I don’t see it as a problem. Other guys from ‘another forum’ recommend them and not only say they fit LCRs not LCs but actually have them fitted to their LCRs and are using them. Anybody here encountered The TT Shop before?

 

[m0rk]

You're right about the requirement 'not' to skim them - there's not the material there to remove.

Sizes look 'right' too

Re: TTShop - they're a forum sponsor & have huge next day stocks available - do make sure they'er supplying the right size, as it's a very common mistake to ship 312mm brakes (as that's what was the default std equipment on most markets LCR's)

 

[storeyd]

I always skim my discs to improve performance and get maximum life out of them.
All you need to do is have the outer lip removed and take a light cut over the rest. This would mean removing around 0.1 mm per side (assuming no grooving). So you need to measure your discs with a micrometer, see how much is on and decide if its worth doing.
For example, if you measure 26.5, then after skimming they are going to be 26.3, which leaves only 0.3 left on them. This will not last long at all, so it would be worth getting new discs. It depends on howmuch its costing you to have them skimmed... For me its free so I do them until they are dead

 

[kempos]

think dealer wanted some more coins off you.
if you have only used less than 1mm in 40k why change them, your pads wont sit on the lip as your last ones didn't and they will be the same size,
have seen people take disks off and angle grind the lip off not skim them which is prob all dealer will do

 

[maty_mackay1234]

I've skimmed my disks but just tidied up the lip with a grinder being careful not to mark the face of the disk! Gash i know