CHARACTERS: Triumph Bonneville Street Twin New engineering. Same soul? The difference between the new Triumph Bonneville Street Twin and the previous Bonne­ville is only one thing: every­thing. It has a new engine, new chassis, new instru­ments, new ride-by-wire throttle, new traction control, new yadda, new razzmatazz, and new glafuncles. But, sure, it’s hard to see…