It's hard to gauge what will and what won't become a classic, whether you're into cars or motorcycles. Some are a given — whether they're a limited-run Ducati or a one-off Ferrari Daytona SP3 – but ...

Fewer than 4,000 rideable examples survive, and prices keep climbing.

Harley-Davidson is famous among motorcycle brands for more than a few things: its muscular chopper motorcycles, long-standing history of innovation, and in-your-face road warrior attitude, to name a ...