PhilB over on the Ducati Monster Forum has over 200k miles on his 2V 900 Monster (same engine).
There are several other examples of >100k miles 900 2v motors.
As was stated above, maintain valve clearances and replace belts when due and the engine will outlast the other components of the bike.
2012 Ducati Multistrada 1200S Touring
Forget the road less travelled. Someone has already been there. Give me the places where the road has not yet gone. There is where you will find the true adventure.
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