• Tuning a Dell'Orto carburettor: the right orderMain jet first, then needle and needle jet, idle last. How to jet a Dell'Orto in a sensible order, with examples from the factory data.
• Reading spark plugs: too rich or too lean?Light brown, greyish white or sooty black: what the spark plug tells you about the jetting, how to get a meaningful reading and where the method reaches its limits.
• Which carburettor circuit works when?Idle circuit, needle with needle jet and main jet work one after the other and overlap. Which part is responsible at which throttle position, and what that means for fault finding.
• New air filter or exhaust: what changes in the jetting?Open bellmouths, a performance air filter or a freer exhaust usually make the mixture leaner. Which parts to adjust, in which order, and why nobody can predict the right jet for you.
• Balancing carburettors on a twin, with and without gaugesHow to synchronise the two Dell'Orto carburettors on a twin, with a vacuum gauge or by feel alone. Step by step after the Moto Guzzi workshop manual.
• Cleaning and overhauling a Dell'Orto carburettorWhen cleaning is enough and when an overhaul is due, which parts wear, what damages a carburettor when cleaning it, and how to check it after reassembly. With a parts list for PHF and PHM.