Like the rest of the Touring line, the Road Glide Ultra rides on Dunlop’s D407 Multi-Tread rear tire that was developed exclusively for Harley’s big rigs. The tire’s construction offers longer-life centre tread compound with softer shoulder compound for improved cornering grip. The rear wheel hub’s Isolated Drive System compensator helps control vibration and noise under all riding conditions, too. But make no mistake, the centrepiece for the new Ultra (as well as the Road King Classic and the Electra Glide Ultra Limited, the latter of which we tested here), is the 103-inch engine.