| Component | Specification |
|---|---|
| Engine | Milwaukee-Eight 107 (1746cc) |
| Oil Type | SAE 20W50 (SYN3 or H-D 360) |
| Oil Capacity | 4.0 Liters (4.23 US qt) |
| Front Tire | 130/60B19 61H (36 psi / 2.5 bar) |
| Rear Tire | 180/65B16 81H (40 psi / 2.8 bar) |
| Spark Plugs | HD-6R10 |
| Battery | 66000175 |
Engineering Highlight: The Sharknose Aerodynamics
The defining characteristic of the Road Glide (FLTRX) is its frame-mounted ‘Sharknose’ fairing. Unlike the Batwing fairing found on the Street Glide, which is mounted to the forks, the Road Glide’s fairing is fixed directly to the chassis. This engineering choice, historically rooted in the 1980 FLT Tour Glide, significantly reduces wind-induced steering input, providing superior high-speed stability and lighter low-speed handling by removing the aerodynamic load from the front fork assembly.
Technical Review: The Milwaukee-Eight 107 Era
The 2017-2022 FLTRX models are powered by the Milwaukee-Eight 107 V-Twin. This engine marked a pivotal shift for Harley-Davidson, introducing four-valve cylinder heads and dual spark plugs per cylinder (HD-6R10). The result is a 10% increase in torque and significantly improved heat management compared to the previous Twin Cam generation. The counter-balanced engine provides a smoother idle while retaining the classic H-D character under acceleration.
Maintenance Guide & Essentials
Lubrication System
For optimal performance of the M8 engine, MotoSpecsLab recommends SAE 20W50 oil. The system requires 4.0 Liters for a full change with filter. While H-D 360 mineral oil is acceptable, the synthetic SYN3 is preferred for better thermal stability in air-cooled configurations.
Chassis and Tires
The FLTRX utilizes a specific 19-inch front and 16-inch rear wheel combination. Maintaining precise tire pressure is critical for the heavy touring frame: 36 psi (2.5 bar) in the front and 40 psi (2.8 bar) in the rear. Under-inflation leads to ‘cupping’ of the tread and sluggish cornering transitions.
Electrical & Ignition
The electrical demand of the Boom!™ Box infotainment system requires a healthy battery. The 66000175 High Output AGM battery is the standard. Ensure terminal connections are torqued correctly to prevent vibration-induced ECU errors. Spark plugs (HD-6R10) should be inspected every 5,000 miles for carbon fouling, a common occurrence in stop-and-go traffic scenarios.
Expert Verdict
The Road Glide 107 remains one of the most balanced touring platforms in the used and new markets. Its combination of the stable Sharknose fairing and the refined Milwaukee-Eight powertrain offers a high-authority touring experience. Rigid adherence to the 5,000-mile service interval is paramount to maintaining the mechanical integrity of the valvetrain and primary drive.