| Specification | Detail |
|---|---|
| Production Years | 2014 – 2021 |
| Engine Type | Revolution X™ V-Twin (Liquid-Cooled) |
| Oil Requirement | 20W-50 (3.1 L) |
| Front Tire | 100/80-17 M/C 52H (36 psi) |
| Rear Tire | 140/75R15 M/C 65H (40 psi) |
| Spark Plug | HD 6R10 |
| Battery Part No. | 66000004 |
The Harley-Davidson Street 750 (XG750) holds a unique place in Milwaukee history: it featured the Revolution X engine, which was Harley-Davidson’s first all-new liquid-cooled platform in 13 years following the V-Rod. Designed with a 60-degree V-angle to keep the profile slim for urban lane-splitting, it marked a radical departure from the traditional air-cooled heritage of the Sportster line.
Engineering Overview: The Revolution X Platform
At the heart of the XG750 is the liquid-cooled 749cc V-Twin. Unlike the traditional 45-degree air-cooled engines, the 60-degree architecture allows for a more compact powertrain, accommodating an internal counter-balancer to manage vibrations. This makes the Street 750 significantly smoother at high RPMs compared to its air-cooled siblings. The SOHC (Single Over Head Cam) design provides a responsive low-end torque curve, ideal for stop-and-go city traffic.
Technical Maintenance & Fluids
Proper lubrication is critical for the Revolution X engine due to its liquid-cooling system and higher operating tolerances. We recommend using 3.1 liters of 20W-50 (H-D 360 Mineral or Syn3 Synthetic). Because the engine shares oil with the primary drive and transmission, high-shear stability is a non-negotiable requirement for long-term gearbox health.
Ignition is handled by HD 6R10 spark plugs. Given the urban-centric nature of this bike, frequent short trips can lead to carbon fouling; we recommend inspecting plugs every 5,000 miles to ensure optimal combustion efficiency.
Chassis and Handling Dynamics
The XG750 utilizes a narrow frame designed for agility. The tire configuration is somewhat unique, featuring a 17-inch front and a 15-inch rear. Maintaining correct pressures is vital for handling: 36 psi in the front and 40 psi in the rear. Under-inflation on the 140/75R15 rear tire can lead to sluggish turn-in and increased heat build-up on highway stretches.
MotoSpecsLab Verdict
The Street 750 is a robust, entry-level heavyweight that bridges the gap between traditional cruiser aesthetics and modern cooling technology. While the braking system was often criticized in early 2014-2015 models, the 2016+ iterations received significant hardware upgrades. For the DIY mechanic, the XG750 is relatively accessible, provided you adhere strictly to the liquid-cooling maintenance intervals and use the specified 66000004 battery to accommodate the tight battery box dimensions.
Frequently Asked Questions
How often should I change the oil on my Street 750?
Harley-Davidson recommends a 5,000-mile (8,000 km) interval, but for bikes used primarily in heavy city traffic, a 3,000-mile interval is preferred to combat oil thinning from heat soak.
Can I use automotive 20W-50 oil?
No. Automotive oils often contain friction modifiers that can cause the wet clutch in the XG750 to slip. Always use a motorcycle-specific Jaso-MA2 rated oil or H-D proprietary fluids.