How to Synchronize the Carburetors on a GSX-R
- 1). Place your GSX-R on a service stand to provide a stable support. Place a large fan in front of the motor. You can leave the motorcycle on its kickstand if you do not have a stand.
- 2). Remove the side fairing panels from your GSX-R, using a 4 mm Allen wrench. Start your GSX-R's motor and let it warm up for three minutes, then stop the motor.
- 3). Remove the inlet screws from the back of the carburetors, positioned just forward of the motor's intake manifolds, using a small flat screwdriver. Screw your manometer's adapters into the carburetors' inlets. Plug your manometer's vacuum hoses into the adapters.
- 4). Start your GSX-R's motor again and turn on your fan to prevent the motorcycle from overheating. Adjust the motor's idle speed to 1,750 rpm, using the idle adjustment knob on the left side of the motor.
- 5). Take note of the manometer's vacuum measurements between the motor's #4 and #3 carburetors -- positioned on the left side of the motor. The mercury levels for both cylinders should be evenly balanced in the center of the meter's gauges. If the levels are not identical, turn the adjustment screw between the #4 and #3 carburetors with a small flat screwdriver until the vacuum levels are even. Balance the #2 and #1 carburetors bodies on the right side of the motor, using the same method.
- 6). Synchronize both carburetor banks, using the adjustment screw placed between the #2 and #3 cylinder. Turn the adjustment screw until all four carburetor's vacuum levels are centered in the meter's gauges.
- 7). Adjust the motor's idle speed to 1,200 rpm, using the idle adjustment knob. Stop the motor and reinstall the side fairing panels, using a 4 mm Allen wrench.
Source...