You will need
  • Synchronization vacuum gauge.
The work of synchronizing carburetors is to establish the same clearance between the throttle valves and bodies of the carburetors at idle. To achieve this, it is easiest to set the vacuum in the intake pipes of the engine. For self-synchronization of the carburetors will require synchronization vacuum gauge. This device consists of two or four vacuum gauges. All its constituent devices designed to operate at a corresponding negative pressure occurring in the exhaust pipes at idle. In addition, the vacuum gauges attarashany equal readings at equal dilution and is equipped with devices to reduce vibrations of the arrows when you change the air flow in the intake pipe.
Two-cylinder engine is a block of two gauges, four-cylinder block of four. More advanced devices to synchronize the carburetors are equipped with displays showing the vacuum in the form of columns. To synchronize the carburetors columns on the display should be the same height. LCD vacuum gauges are equipped with coarse and fine modes of operation.
Before synchronizing the carburetors, adjust the door actuators. For synchronization of the carburetors, remove the fuel tank air filter (if necessary) and locate where the connecting pipes of the vacuum gauge. The old and simple models of motorcycles you can find them on special plugs on the intake ports. On modern motorcycles, the vacuum in the manifold is used to control various devices. Use the tubes of these devices by connecting them to the vacuum gauge via the tee. When you do this, remember what the pipeline is, where was filmed! If space connect vacuum gauge remote may have to remove the carburetors.
Start the engine and warm it. Valves vacuumers adjust so that they are less fluctuated, but at the same time respond to the slightest change in vacuum. Perhaps this procedure will be repeated with further synchronization of the carburetors. If the arrow of the device will not respond to changes in dilution, loosen the valve, if it starts to oscillate – pull valve. Check the idle speed, which are calculated on the engine and install the rpm. Error in setting the speed will lead to about sync the carburetors: the readings will show on the achieved synchronization, but the speed changes, this synchronization disappears.
Different engines have different procedures for the adjustment of the synchronization of the carburetors. This is typically achieved using 3 screws. Base screw located between the carbs and control the dampers I and II of the cylinders. In four cylinder engines the second screw regulates the damper cylinders in pairs I-II and III-IV. The third controls the valves III and IV cylinders. First, adjust first the screw, then the third, and last but not least – Central.
Upon reaching the uniform readings of the vacuum gauges test the synchronization of the carburetors. To do this, sharply increase engine speed and reset them to blank. Synchronization of the carburetors will not disappear. The gauge needles should return to the same for all position.