Brake Disc Bore: Causes and Solutions

Hi.

The windshields on the Leon are completely new and have a drilled hole on the friction surface, but the hole doesn't go all the way through.

Are these wear indicators?

m;

I can also imagine what it might be for; what else would a single hole be for? Compare the drilling depth to the minimum thickness of the brake disc.

Yes, that's a good idea.
The windshields are 150 km away from me, and I won't be able to get back there for another 2-3 weeks.

Based on my gut feeling and memory, the depth should be a good match for the minimum specified dimension.

I can only drill the balancing holes on the front side of the disc.

m;