Balancing pistons

I am at the stage where I am balancing pistons and rods.

Any advice on where to remove weight from the piston assembly?

I need to remove 2 grams (doesn’t sound a lot but it represents a fair volume of aluminium!)

I have seen an opinion about removing weight from the bore of the gudgeon pin, however they are hardened and a file won’t touch them!
Anyone tried a small grinding burr on the inner bore? Or any other ideas?

Otherwise, I reckon I will remove material from the skirt just below the gudgeon pin bosses.

Any opinions?
Thanks
Bruce

If i am not mistaken yellow is a good place to grind and green is also fine but not recommended(in accordance to attachment). And try keeping things even.

As what tool to use i would suggest a small orbital sander with fine grade and if using a grinding burr i would be very careful because 2 grams can be removed fairly fast.

Will also work but be careful once again.

Hope this helped and hope i’m right.

Tim

In the end, I didn’t fancy taking the material off the pistons - especially off the crown!

So I dug out a very old small grindstone and ground the material off the bore of the gudgeon pins. It was a bit tedious but it worked.

Thanks
Bruce