Engine Oil
Synthetic SAE 5W-40 API SJ or higher - any brand that meets this specification is fine as the X9 does not have a wet plate clutch or gearbox. Car oils are perfectly OK from the major brands but Piaggio recommend Selenia. Drain and refill with the bike on it’s centre stand and fill to the top mark on the dipstick. Replace the filter on all but the 250 Honda engines and clean the strainer inside the drain plug aperture at each change. Dip  stick/filler hole is on the RH side on 250 SL and 500 models and LH side on  125 and 250 Evo models.

Rear Hub oil
The rear hub uses ordinary car hypoid 80W/90W gearbox oil (not ATF)

Coolant/Antifreeze
This must be used in a reasonably strong solution at all times regardless of climate to prevent internal corrosion of the waterways and radiator. Any Mono-ethylene glycol in a 50% solution with water will be more than sufficient for temperatures down to -20 degrees celcius. Blue antifreeze generally lasts for 2 years and red antifreeze lasts for 5 years.

Brake Fluid
Any synthetic SAE J1703 DOT 4 or higher is fine. DOT 4 fluid will last 2 years before requiring to be changed, the newer DOT 5 lasts 5 years.

Fork Oil
Hydraulic oil SAE 20W (thick) despite what it says erroneously in some owners  handbooks.

General Greases
Keep the centre stand idler wheels greased using conventional Moly HM grease and the brake lever pivots with white calcium soap grease as this does not soften or rot rubber parts. Copperslip is recommended whenever  bolts are replaced to prevent corrosion caused by different metals.