The Street Twin first. The reason for its success, Triumph says, is a mix of entry-level price (for the British brand at least), classic looks, and easy demeanor. If there was a recurring criticism of the 2016 Street Twin, at least from some areas of the media, it was the bike’s lack of oomph. So the biggest change is the engine. Triumph call this its “High Torque” 900cc motor. There is, it says, 18 percent more power, roughly 10 hp, taking the claimed power to 65 hp. This increase is mainly delivered with help of a 500-rpm rev increase to a new redline of 7,500 rpm. Studying the supplied graphs, peak power is up, but in the 3,500-to-5,500-rpm rev range, where even Triumph says the bike will spend most of its life, there is only an increase of 0 to 4 hp. Peak torque is the same, but the curve is flattened, so it offers increased torque over a wider range.