| Component | Specification |
|---|---|
| Engine | Revolution Max 975T (Liquid-cooled V-Twin) |
| Production Years | 2022 – Present |
| Oil Type/Capacity | Screamin’ Eagle SYN3 15W-50 (4.3 L) |
| Front Tire | 100/90-19 57H (36 psi) |
| Rear Tire | 150/80B16 77H (42 psi) |
| Spark Plug | NGK LMAR9AI-8 (Gap: 0.8 mm) |
| Battery | OEM Part #66000305 |
Engineering Highlight: The Stressed Member Chassis
The Harley-Davidson Nightster 975 (RH975) represents a radical departure from the traditional loop-frame architecture of the Sportster lineage. A key engineering highlight of this model is that the Revolution Max 975T powertrain is a stressed member of the chassis. By eliminating a traditional frame and mounting the front frame, mid-frame, and tail section directly to the engine, Harley-Davidson significantly reduced the motorcycle’s weight and increased torsional rigidity, resulting in a significantly more agile handling profile than its predecessor, the Iron 883.
Technical Maintenance Specifications
Proper maintenance of the RH975 is critical due to its high-revving, liquid-cooled nature and integrated electronics. As the Editor-in-Chief of MotoSpecsLab, I recommend adhering strictly to the following technical parameters:
1. Lubrication System
The Revolution Max 975T engine requires high-thermal stability lubricants. We specify Screamin’ Eagle SYN3 Full Synthetic 15W-50. The total refill capacity with a filter change is 4.3 liters. Ensure the motorcycle is upright when checking levels to avoid cavitation or overfill issues common in semi-dry sump systems.
2. Wheel and Tire Assembly
The RH975 utilizes a staggered 19-inch front and 16-inch rear setup to maintain a classic cruiser silhouette while providing modern grip.
- Front: 100/90-19 57H at 2.48 bar (36 psi).
- Rear: 150/80B16 77H at 2.90 bar (42 psi).
Maintaining precise pressure is vital for the lean-sensitive ABS and Traction Control systems.
3. Ignition and Electrical
The engine utilizes high-performance NGK LMAR9AI-8 spark plugs. The gap must be precisely set to 0.8 mm to ensure efficient combustion across the variable valve timing (VVT) range. For battery replacements, use the 66000305 AGM battery to handle the high cranking amps required for the 12:1 compression ratio.
Editor’s Verdict
The RH975 is a masterclass in modernizing a legacy brand. By moving the fuel tank under the seat to lower the center of gravity and utilizing a liquid-cooled DOHC engine, Harley-Davidson has created a technical platform that rivals European naked bikes while retaining American cruiser DNA. Regular maintenance using these exact specifications is the only way to preserve the performance of the Revolution Max platform.