Over the years I've tried to come up with tricky ways of fixing stuff. I've never been able to understand what happens inside the bore of a Brembo master. What evil things can grow in brake system. Just the smell alone can make you sick. I have an unobtanium goldline rear master for a TT. The piston didn't come out with some of my conventional methods. So I put it in a vice (with aluminum jaws), center punch the piston, drill an 1/8 inch pilot hole, then a number 9 drill, 6x1mm tap, use a slide hammer. Give it a couple of pulls and victory! Look at the stuff on the piston! Also rebuilt the front master. Where does all the rust come from? Lou

Nice work Lou!
Very good save of a rare piece.
Paul

In the past I have used a piece of aluminium dowel up through the banjo end after removing the fitting then knock out the piston ?

Sam

Lou, The crap comes from the water the brake fluid absorbs from the air and its reaction with the alloys that make up the cylinder, piston, and washers. It's all a reminder to change your fluid regularly. Silicone fluid would seem to be an answer but while it doesn't absorb the moisture it doesn't exclude it either so the water still corrodes things when it gets in.

Hi Guys, I know hydroscopic brake fluid. I just think it's funny how nasty it gets. I think the problem with silicone is also boiling point is lower than DOT 4. I remember Harley used it for a while and then stopped. Sam how big was the dowel? The hole on the banjo end is tiny. Lou

Come to think of it it may have been a drill I used, and as large as the hole would permit. The drill or dowel will pass through the spring and then up against the piston.