This is a Yamaha Blaster piston that was part of an experiment to see what a boost port in the piston would do.
All work on it was done in a my home workshop drillpress.
You will notice it is badly scratched and scarred.
If you are going to experiment until failure, do it on something cheap, or worn out.
Also do it one small step at a time to see what works and what doesn't.
In spite of a well worn and scratched piston and bore, this worked very well:
My son and I put the piston back into the engine and took it back out for a ride to test the effect.
Every time we upsized the slot or added new holes, we re-assembled and test drove the Blaster:
The upshot of this, we learned exactly what and how much made this engine work better.
This piston was in and out of the engine at least 6 times in an afternoon, with about a half hour of riding each time it was together.
Notice the plastic shopping bag that assures the clip and dirt do not fall into the bottom end:
End result was that this was too much, but now we know. Glad we did it to worn out parts.
These air cooled 2 strokes, with no cooling shroud or cylinder head mount are the simplest top end to work on.
Only takes minutes to do anything. I can strip a CG engine out of the frame and into pieces in less than an hour.
So you want to experiment on your new engine? Drill the piston?
Put it together stock, break it in properly, and order a new piston, or even a new piston/cylinder/head.
Then is something fails, you are not waiting for shipping.
But don't let it fail.
Start out stock, and do your mods one step at a time, so you know what works and what doesn't.
Steve
Just noticed I've got my gunslinger pants on...
