Idle Adjustment

With ignition timing correctly set and engine at normal operating temperature, proceed as follows:

1. Using a CO meter, set CO level to approximately 2%. If this uncorrected idle speed exceeds 1000 RPM, the CO content should be reduced; if idle speed is lower, the CO content should be increased.
2. Remove air cleaners and housing and using a suitable balance meter (flow meter), adjust the primary throttle plate of each carburetor to equal flow.
3. Reinstall air cleaner and housing. Adjust idle mixture to 1.0-1.5% CO with engine running smoothly at an idle speed of 900-950 RPM.
   NOTE: Each exhaust manifold is provided with a connection for sampling of exhaust gas. These connections are closed with a bolt. Remove bolt and sample exhaust gases by inserting probes.
   Fig 1: Firing Order

   Courtesy of BMW OF NORTH AMERICA, INC.