The oil filtration on these engines is minimal as the Filter oil feed is a spur off the main oilway to the Crankshaft and if the oil gets dirty then any contaminants collect in the centrifugal Crankshaft Filter until they block off the oilways and the Big Ends fail. It's not possible to clean these oilways without splitting the engine so 5 litres of oil at about £35 every 1,000 miles is much cheaper than a pair of Con Rods (outer track of big end bearing is the Con Rod eye) A pair including Crank Pin come in at exactly £1,181.25 + VAT and in addition you would expect to replace Main Bearings (2 x £73.96+VAT) and then there is Labour, total has to be in the region of £2,500 plus.
Check parts and prices at Mdina Italia at
https://www.mdinaitalia.co.uk/ who keep a large range of parts including Con Rod assemblies.
When I first bought mine I phoned Silkolene Technical Department and their man checked in his book and told me that the Ducati Bevel Drive Vee Twin engines had a * against the entry confirming that they should only ever be run on monograde oil and not multigrade due to the Roller Bearing bottom end. Now on the Forums there is almost as much argument about oils as on the BMW and most other Forums, but I've always used the Silkolene Hardwick high detergent straight 50 and am happy with this.
Note that the original Manual that came with the bike from Ducati does say to use 20/50 multigrade but if you do and the bottom end goes it's your pocket that will pay for it!
But when you are riding and winding the engine on, listening to the exhaust from straight through Conti's there is little to beat them.
Edit was to add note about the Bike's Manual.
