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You can do a search for Gordon Jennings PDF and get a downloadable version right online for free if you hate spending the money for it. The newer revisions also have some add-ins by Eric Gorr. Pretty good reading if you want to learn a lot about the fundamentals of two strokes. Some other good reading is A. Graham Bells book, trying to remember the title.

I mentioned earlier how technology has affected some of Jennings theories. Two that come to my mind the most at the moment are advancements in reed induction, which he covers very little and piston ring materials/design. Reed petal and cage designs have come a long way since the 60's and allow for a much more controlled and larger intake charge. Most of Jennings work discussed is on piston port engines. As far as piston ring design, Jennings mentions standard exhaust port widths of 60% with extreme cases being in the 70% range with very carefull considerations on port designs. Today we can realize standard port widths in the 65-70% range with the extreme (drag) port widths in the 75% range without the amount of ring failures seen in the past. This is one reason I believe so much emphasis back then was placed on larger bores being the way to go. The larger the bore the wider you can make the effective exhaust port and thus the more power you can produce. Horse power is a product of many variable, engine speed being one. But the best method is to find ways without increasing rpm, to increase the BMEP of the engine. In other words increase it's volumetric efficiency through more efficient porting, pipes, head chamber design ect. Performance two strokes have come a long way since the days of Jennings studies.

Very good topic Senator....Thanks!