Willie,
Don't know if you've purchased your gasket goop yet, but due to environmental or health concerns, some have been taken off the market. I don't think that Yamabond is currently available, unless it's old stock. I couldn't find it here for that reason, and learned that it was no longer sold. The folks who made Yamabond, now put out their own replacement, called Threebond 1194. You want the 1194 product. It's the same as the Yamabond basically, but without the lead content. I see on the web that it's sold in the states...some Yamaha dealers list it. I've had excellent luck using the Threebond, no leaks on the three saws that have it as the base gasket now. I spoke with the manufacturer about using it for the cylinder gasket, and they said it was designed for such use.
Yes, the transfers are the openings 90 degrees to the intake and exhaust ports. When the piston travels down, it pushes the charge from the intake down into the crankcase, and the pressure forces it up the larger lower transfer, through the channel, and it comes out above the piston rings and then gets compressed as the piston rises before ignition. There are what's called open and closed transfers, depending on whether the whole transfer channel is open to the cylinder, or it has two separate openings. I assume yours is a closed transfer type cylinder. The reason why the upper transfers are angled toward the intake, is because as the charge enters above the piston, the exhaust port is still open, so instead of the intake charge flowing out the exhaust port with the after combustion gases, it actually travels around the upper part of the cylinder and helps push out the exhaust, a very dynamic part of the two cycle process, called scavenging, then the remaining charge gets compressed to explode. Some of the fresh charge gets lost out with the exhaust, one of the efficiency problems of two cycle engines, and a reason why they are considered somewhat environmentally unfriendly. The reason why racers put tuned pipes on their saws, is because a good portion of the unburned fuel that gets lost out the exhaust, actually gets kicked back into the cylinder to be burned. Pipes up the efficiency process. So much for the two stroke primer, I'm far from being an expert.
There is a short section of cylinder wall under the lower transfers, before the base. By shallow grinding that away the whole width of the transfer, the charge can leave the crankcase a bit sooner, and probably with greater velocity to travel up to the upper transfer opening. Grinding away on any material inside the transfer that will allow better flow, is advantageous. There is extra metal in there that can get removed. It can help to picture the flow of charge as how water would respond, flowing better around smooth curves than it would against abrupt angles and obstacles. One of the big aspects of modifying an engine, is improving flow of the gas/air charge, and exhaust. The easier the fresh charge moves at a subsequent greater velocity, a then larger amount of it will get compressed to ignite, which equals more power. A certain percentage of the charge also enters the upper part of the cylinder by traveling through the inside of the piston skirt, the reason why there are openings on the sides of the piston. Removing material on the underside if the piston, enlarging the openings, anything that impedes flow, is also a modifying step, and you can lose a lot of piston weight that way as well....a very positive thing for increased rpms. You just need to consider how much you can take off before strength is compromised, or you leave yourself with an open port situation when the port should be closed.
Something along those lines
Jay