XJ750 Seca Master Cylinder Piston Popper

Ever tried to get a stuck piston out of that goofy remote master cylinder on a 750 Seca?

I was recently trying to get my spare MC apart to see what it looked like and found myself with a stuck piston. Because these aren't like a normal piston, there is nothing to get ahold of to try pulling it out, and I couldn't get a good enough seal with compressed air to get it to move. Plus using air often ends up launching the piston into low earth orbit if you do manage to get enough pressure to pop it out, and you may never see it again.

So, I decided to use the same principal as the wedge I made for removing the caliper pistons on my 900 but on a smaller scale. There is a 7.5mm hole in the top of the piston, so I made a 7.5mm wedge with a tapered bore that will cause it to expand like a drywall anchor when you thread a 4mm bolt into it. A 60mm long bolt seems to be the perfect length. Insert it into the hole and tap it with a mallet so it is snug and doesn't spin, then tighten the bolt as much as you can to wedge it in place. Gently pry up on the head of the bolt with a pair of pliers. The piston should follow it out.

Here's the model on Thingiverse.
https://www.thingiverse.com/thing:7402233

And here is the illustration of how it works.

(Don't forget to take the circlip out first. Mine was so gummed up with gunk it was hard to see.)