Touring motorcycles with their plethora of luxury features tend to be the flagship models for manufacturers because touring riders demand comfort, handling, big power, weather protection, and storage space – and they’re willing to pay for it. Thanks to the Project Rushmore upgrades first seen in the 2014 model year, the ‘Glides have delivered first-class accommodations and the technological features touring riders expect. Just take a look at the Boom! infotainment system and the LED Daymaker headlight. Be it with a frame-mounted fairing as with the Road Glide or a fairing-mounted one on the Electra Glides (among others), the Harley-Davidson touring line commanded a large portion of the luxury touring market. Still, the Twin Cam engine had begun to show its age.
Well, all that changed in 2017 with the release of the Milwaukee-Eight engine. The most obvious change in the powerplant is right there in each engine’s model name – four valves per cylinder for a total of eight tappets escorting the combustibles in and out of the party. The Twin Cam 103 engine grew to 107 cu. in. thanks to its new bore and stroke of 3.937 in. x 4.375 in. (99.999mm x 111.125mm) while the 110 jumped up to 114 cu. in. via its 4.0-in. x 4.5-in. (101.6mm x 114.3mm) bore and stroke. Besides being larger in displacement, the engine’s four-valve head is said to flow 50% more than the Twin Cam’s. Two different variants of the M-E engine were created to handle the heat the expected touring loads the bikes would handle. The Twin-Cooled heads utilize liquid-cooling from water-jackets around the exhaust valves while the standard M-E uses oil to carry heat away.
In response to customer requests, the Milwaukee-Eight engine is a claimed 75% smoother at idle. Once underway, vibration is not an issue until the upper reaches of the rpm range. While one might expect an engine which Harley states has 20% more flywheel mass to rev more slowly than before, that would be wrong. Instead, blipping the throttle at idle has the engine spin up much more quickly than previous Big Twins from the Motor Company. Out on the highway, the comparison to the Twin Cam engine is all positive. Coupled with the torque-assist clutch, which reduces lever effort by a claimed 7%, the riding experience is much improved.
Harley’s engineers also took the opportunity to upgrade the suspension. The shocks are now large-piston emulsion-style items, with the left shock gaining a knob to hydraulically adjust the rear preload. Gone is the air-adjustable preload that could leak over time, allowing the suspension to settle and use up its travel. Now that the left shock features hydraulically adjustable preload, the rider simply cranks on more or less preload, and it stays set, forever. The range of preload adjustability is now 30% larger than previously.
Harley-Davidson’s big changes to its touring line have taken already comfortable and tricked out mileage gobblers and increased the level of performance. The Milwaukee-Eight engine is, quite simply, a joy to operate, delivering ample power across the bagger and touring rig offerings. The suspension contributes to a more enjoyable riding experience for both rider and passenger. Rather than an annual, iterative update to its existing line, each of the Milwaukee-Eight-equipped motorcycles we had the pleasure of riding felt like a different motorcycle with the boost in power and handling. For this reason, the Harley-Davidson touring line wins the MO Best Touring Motorcycle of the Year.
However, the K1600 outfitted in either GT or GTL guise is sportier than anything else in the Touring class, and consequently, still deserves praise. Every facet of the bike, from the Duolever front end and optional electrically adjustable suspension, combine to deliver an exhilarating ride at high speeds in both the straight up and down and deep lean angles. The inline six-cylinder accelerates like nobody’s business and provides intoxicating music for gear head’s ears.
This year, BMW may have been bested in the touring class, but one thing we know about the company is that it never sits still. We expect that, like it has in the past, BMW will find a way to set the touring bar higher, giving its competitors something to aim for.