Oversize pistons...

Ok guys, It has been awhile since I have been on, but I am currently knee deep in engine parts on my GT550L and I am a little curious about oversize pistons.

On the top of my pistons there is a .040 When I look online, most of what I find says that a .5 is the first overbore size. However I have seen an ad that says the .5 is the second overbore. What I am trying to find out is...

1) Are my pistons already larger than standard?

2) What is the size of the first overbore, and what are the sizes afterwords?

3) finally, What is the largest overbore, and will a standard head gasket work for an overbored cylinder?

this was posted on oldskoolsuzuki.info today in the 2 stroke section

Hello, Can someone tell me the maximum size pistons you can fit? I have just stripped down my engine and the current pistons have 1.0 stamped on them, there are some scores on the bores so can I have it bored out anymore?

Thanks

Hi guys,".040"stamped on your piston Kyle might suggest imperial,therefore 1mm oversize & probably a second re-bore as 0.5mm is normal for re-bore sizes.Hope you sort it matey.