What Chuck said. My understanding is that the purpose of that is to have all 4 butterflies in the same position as a starting point. Static synch I believe is the technical term. Also called bench synch. The vaccum synch is more important and takes into account and adjusts for slight differences in individual cylinder conditions. When done properly the bike runs much smoother especially of the synch was off.
This of course depends on a proper carb rebuild, good sealed intake tract, etc. It really should be a systematic approach to save headaches down the road. Carbs should also be synced after valve adjustments also.
This of course depends on a proper carb rebuild, good sealed intake tract, etc. It really should be a systematic approach to save headaches down the road. Carbs should also be synced after valve adjustments also.

