Not just for noise, PC. Secondaries are also used for power restriction. Take a look at the French market Supermoto map, or compare the 990A to the 990R map secondary position table to see how it works.
Originally Posted by PowerCell
Tuning with a dyno allows you to trim fuel for the entire RPM range...
Secondaries are soley for noise control... period.
FI systems don't require high intake velocities through the throttle bodies... there are no venturies.