Seven years after the previous television series starring Ewan McGregor and Charley Boorman undertaking an epic motorcycle trip, “Long Way Up” sees the convivial duo (backed by a support team that often offers subplots) tilt at riding from the southern tip of South America all the way to Los Angeles. A novel addition to their schtick is that they’re on prototype Harley-Davidson electric motorbikes. The eleven episodes of Long Way Up make for a pleasant, often fascinating viewing experience, the highlights being spectacular scenery brilliantly shot; the genuine camaraderie of McGregor and Boorman; the insights into our future electrified world, as they struggle to charge their bikes on an underdeveloped continent; and admiration of the riders’ pluck. The first half of the season struck me as more exciting, with the final two episodes of dramatic passage through cartel-ridden Mexico proving to be a little flat, but overall, Long Way Up is an intriguing, warm-hearted travelogue.