Useful articles for two stroke engines:

1) Ignition Timing by Bill Unger.

2) Bike myths.

3) Basic 2 stroke Tuning by Eric Gorr.

4) The Art of Squishing things until they give power by Dale Alexander.

5) More power to the Air-Cooled RD by David Freist.

6) Torque and Horsepower by Bruce Augenstein.