So after doing a little research, the notch above you intake port may not be a bad idea. It is there to help direct the gas-air mixture to spark plug, helps with quicker throttle response but me personally if your running reed valve, id complete 3rd transfer port. From what your telling me with the double gaskets and the notched cylinder you may have a fred engine or someone copied how he builds his engines because that's what he does and if your head is an aftermarket high compression head, with the doubled gaskets , its probably a 7.0 head. They double the gaskets to elongate the cylinder which could help with top end speed. I dont quite understand exactly why that helps, ive just come across some videos stating that. You should look up some Fred videos, I know the guys at Zeda seem to like to bash his engines but he has been doing engine builds well before Zeda so I take what he says as knowledge and truth. By the sounds of it, you may have got a great deal on a nice engine, those copper gaskets alone will run ya $20 a pop. Some time when you can, id love to see a oil of it. Listen I haven't been doing Bicycle engines very long, ive spent a lot of my life in the country working on and racing 2 strokes, sense ive moved to the city, this is about all I have room for lol but I love it. These little engines are a blast to work on and sharing info with you and others makes it even better. I haven't got my engine back together sense balancing the crank, my gaskets won't be here until tomorrow but I just spent the better part of the morning running around finding good aftermarket bearings for my engine. Its a good idea to replace the bearings with good aftermarket one because though the bearings in these engines aren't that bad, their the life line of these engines and upgrading them is a good idea. Anyway let me know how your making out and ill do the same. Cheers my friend