Gear-driven camshaft Benelli

We ran a feature on the top ten prettiest engines a week or so ago.

We missed one.

This 1950s engineering jewel is the Benelli Leoncino or, to translate, 'Little Lion'. The dinky 125 revved to a dizzy 18,000 rpm to make its slightly less dizzy 12bhp. It also featured a four-speed gearbox and nifty valve adjustment (rockers on eccentrics). But how beautifully proportioned are those neatly arranged gears to drive the single overhead camshaft? Work of art.

But, weirdly, the same bottom end could carry either a two-stroke or four-stroke top end, giving the manufacturer two bites at the apple. The two-stroke is less pretty...