This video shows the two step process on how to preform the proper carburetor synchronization on the Honda CB350 / CL350 family of motorcycles as well as the CB450 / CL450 / CB500T series of bike. The process is shown on a CB350 set of carbs, however the same exact process is used on the CB450 carburetors as well.
Step one - setting the idle speed synchronization, aka "bench sync." Step two - adjusting the progressive synchronization, which means having the carburetors open and close at the same rate when the throttle is twisted.
New throttle cables and a throttle sleeve ensure smooth and proper synchronization.
CL350 / CB350 Throttle Cable: http://www.common-motor.com/honda-cb-cl-throttle-cables
CL450 / CB450 / CB500T Throttle Cable: http://www.common-motor.com/honda-450-throttle-cable
Nylon Throttle Sleeve: http://www.common-motor.com/honda-throttle-sleeve