Bend the stop on the reed out a bit. That way the reed will open more and allow more fuel in. BE CAREFUL and don't bend the stop out too much or it'll interfere with the connecting rod and crank pin.

Switch your carb. The stock carb is tiny. There is a bigger carb that fits the monting block perfectly. WT438? or a WT348? Can't remember--it's been awhile since I did that.

Get a new ring from Frank Bowman in Farmington, NM. Better seal and less compression blow-by. Makes a few hundred RPM difference.

Mix your oil at 32:1 or 40:1. Oil makes power. It also carries away the heat.

Switch to electronic igniton--lighter.

A little here and a little there---before ya know it--you got a screamer on your hands.