5. FUEL SYSTEM AGILITY CITY 125 Remove the needle holder and jet needle. Be careful not to damage the vacuum diaphragm. Jet Needle INSPECTION Inspect the needle for stepped wear. Inspect the vacuum piston for wear or damage. Inspect the diaphragm for deterioration and tears. Vacuum Diaphragm Vacuum Diaphragm Vacuum Chamber Cover ASSEMBLY Install the vacuum piston/diaphragm in the carburetor body. Install the spring and then install the vacuum chamber cover. Tighten the two screws. 5-7