This one is ported for strong mid range. The transfer ports are pulled slightly rearwards and the exhaust port is widened on top. Squish band is set to a minimum, 0.55 mm, and cylinder pressure will be on the high side since it doesn't need to rev terrible high. These cylinders provides max power @ 9800 rpm stock. The combination with 3 mm longer stroke and tuned exhaust will give a meaty mid range for good driveability. It will also have a fixed electronic ignition system, which I modify myself for an automatic retarding curve, starting at about 30 degrees BTDC on idle and falling to about 15 degrees on full rev. This is a solution that is used on many small classic bikes here now.
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