Discussion Modification for Honda Singles

Here's hoping that you're pleasantly surprised...

 

If I were setting out today to achieve the result you are after, I would probably do the same as you are doing.
However when I modified mine back in the early 70's, I didn't want to spend money on the big bore kit available from Poweroll.
I had access to a free 305 sleeve and had the use of a lathe in the local high school metalwork room. A standard 750 piston was a lot cheaper than a big bore piston from the USA. Of course I had to turn the top of the piston down to get the compression ratio I wanted. I had one that was 13:1 for when I was running on alcohol and one that was 10:1 for running on petrol.
I understand that your approach is the simplest and probably cheapest option today, but the way I did it back then saved me a lot of money.
I don't remember the thickness of the lower skirt after it was bored out half a millimetre, but it certainly wasn't thin enough to cause concern.
I wasn't offering myths about how the conversion should be done. I was simply describing what I did. Just because it worked for me doesn't mean it is the best approach for someone else at a different time when the available resources might have changed.
One other thing that i didn't mention before was that I was running the carburettor from a 175 Honda, probably the XL175. Since I had already fitted the Poweroll stroked crankshaft, I had 175cc.
However I still had 125cc cast on the side of the cylinder, so I could tell 125 and 175 two stroke riders that the reason I beat them around the race track was that I tried harder.