Bimota sometimes uses Ducati engines and transmissions, I don't know if it's an off the shelf group in this case, but a dry clutch system is one of the distinguishing traits of Ducati powertrains. The clack clack are the plates of the clutch that are not kept in place by oil and theyr sound comes out clearly from the frequently completely perforated or slotted clutch enclosure.
Older engines just have that noise, i got a early 90s fzr and you can reslly hear that thing moving around opening and closing the valves, something to do with have carburetors i believe
