Piston Pin Problems

A few weeks back, the left piston slipped right out with a few taps of a hammer. Not so for its sister, (or should I say evil twin). The right one didn't budge. I smacked it good with a hammer a few times. Nothing. And yes I have the circlips out.

So now I've made a piston puller and tried that. Yes! The pin is sliding out (with lots of torque applied).

But after an inch or so, she didn't want to cooperate anymore. I really cranked on the puller and she just won't move. Is this normal?

And once again, I chipped off some aluminum. This stuff is more brittle than a rose dipped in liquid nitrogen. The large socket dug into the piston just above the pin as seen in the picture above. At that point, I didn't really care. I just wanted the piston pin out. I can always get a new piston.

So now what?

I know some mechanics and bike enthusiasts out there are cringing. I look at at this as a learning experience. I'm not afraid to make mistakes, just as long as I learn from them. Besides, even if I turn this into a parts bike, I'll consider it the best small engine repair course that $300 can buy.

I'm going to make a running list of all the stuff I break (for fun and for motivation to be more careful).

1. Chipped piece off engine case (cosmetic)
2. Chipped piece off clutch hub (may need replacement)
3. Chipped piece off right piston (will need replacement)
4. ?