It might be worth mentioning a flash from the past .A certain old hot saw builder on the west coast,one Art Martin had one of if not the hottest cookie cutter on the coast for years .It was an 090 running highly modified 1/2" chisel chain .Art only slightly mentioned it on a web forum I won't mention or access the rest of my life .
Evidently it used a windowed piston with reed valves in the transfers and a huge carb. No pipe .Art said it would dead stick at about 9,00o .It evindently was more a torquer than a hot rod .That big chain taking a bite about like a bike engine saw did the trick .Other than that Art didn't give out any real secrets on what he actually did.They were buried with him .RIP Art. BTW on one of my hard drives I have a picture of that chain as he only put it on that site I mentioned one time .I'll never try to duplicate it though .
I love listening to stories like such. Thank you for sharing that. My input. I agree 100 percent on that engine behavior. I have some input on that. As we all know, these motors are derived for torque and low rpms and more importantly, a compact design.
A modern hard hitting 2 stroke requires a few KEY factors to horsepower.
1. Square or under square design.
2. “Long rod” rod ratio.
3. Good transfer volume, timing area and shape
4. A pipe that takes best advantage of the blowdown figures.
5. No excessive amount of primary or secondary compression. I’ve lost power doing this.
6. A harmonically sound rating assembly. The amount of power lost they bad/ excessive harmonics is drastic. (Vibrations are bad in other words)
All modern 2 strokes deal with these issues.
My motor does not meet any of those points lol. But it’s compact and Torquey. Not to mention it’s an outdated design. Transfer volume and flow in my arbitrary opinion, is the biggest offender that hinders this motor ability to rev. Being heavily
Oversquare is second on my
List. I have tried to fix by adding extra ports and widening the ports plus windows. . (I did not show this).
I’ve build different kinds of 2 strokes. Other than trial end error, just by looking the arquitecture of a modern 2 stroke and I quickly
Realized why my motor wouldn’t rev or perform as I would think. But the engineers were and are always one step ahead of us. They motor was purposed for work. We all know this. A lot of what I’ve said many people here already know. I suppose it further points out how much of an ape this cylinder and motor are in nature.
Btw, in have gotten food results adding transfer volume on this motor before. On other ‘motors it sometimes kills the powerband. Not all motors like the same mods as we all know.
Thanks for your input!
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.. that’s some very good handy work you have there . 
