1200/1250 LC Front Disc brakes

[Jverdoes]

Hi all,

I've bought a set of used discs for my cast front wheel but the sizing is different compared to the old discs.
The pad contact area of the old discs and the discs currently on my spoked wheels is 34mm but the discs I bought are 40mm.
All the other dimensions, like the OD(305mm) and bolt centers are exactly the same. The thickness on both discs are about 4.4mm so that's all good.

Are these OK to use on my spare set of wheels

 

[Santa-2512]

If the new discs are wider than the old,

you will need to check the clearance between the diameter of the disc and the brake caliper , thats where you will have issues

Smaller pads on a large disk will give you a wear ridge in the disc, if you look at your car, you will see a wear ridge at the top and bottom of the brake

disk , ie the pads swept area is smaller than the disc.

Looking at the new discs, it looks like you have a wear ridge at the top of the disk,

whats the thickness of the new disc, and is it in spec?

The problem arises when the swept area is bigger than the disc,

what will happen then, is you will wear a groove onto your pad, which could cause binding as the disk will be sitting inside the pad

Have you checked the part numbers on real oem, The larger unit may have superseded the smaller units

 

[Jverdoes]

If the new discs are wider than the old

I had a look on eBay for differences between the models and yes, they have sent me the wrong discs
These are for the pre-LC 1200 models and are wider than the LC discs.