| Specification | Data |
|---|---|
| Production Years | 1986–1987 |
| Engine Type | Evolution V-Twin (Air-cooled) |
| Engine Oil | SAE 20W50 HD 360 Mineral (2.8 L) |
| Spark Plug | HD 6R12 |
| Tire Front | 100/90-19 57H |
| Tire Rear | 130/90-16 67H |
| Battery | 65991-82B |
A Brief Moment in Engineering History
The Harley-Davidson XLH-1100 holds a unique position in the Milwaukee manufacturer’s timeline: it was the first ‘Evolution’ engine Sportster to feature a large-bore displacement. Produced for only two years (1986 and 1987), it served as the bridge between the aging Ironhead era and the standardized 1200cc Evolution powertrain that followed. Unlike its predecessor, the XLH-1100 utilized alloy heads and cylinders, which drastically improved heat dissipation and reduced oil leaks—a hallmark of the ‘Evo’ revolution.
Technical Engineering Analysis
The XLH-1100 was engineered to provide a more reliable and smoother power delivery than the 1000cc Ironhead it replaced. By utilizing hydraulic lifters, Harley-Davidson eliminated the need for constant valve adjustments, a significant leap in maintenance ease for the average rider. The 1101cc displacement was achieved via an 85.1mm bore and 96.8mm stroke, offering a torque-heavy profile suitable for both urban commuting and light touring.
Maintenance Guide & Specifications
Maintaining the XLH-1100 requires adherence to period-specific lubricants and tolerances to ensure the longevity of the alloy components.
Lubrication System
The Evolution engine in this model relies on a dry-sump lubrication system. For optimal protection of the internal bearings and valvetrain, MotoSpecsLab recommends SAE 20W50 HD 360 Mineral oil. The total capacity is 2.8 Liters. It is critical to check levels when the engine is at operating temperature to avoid overfilling.
Chassis and Tires
The XLH-1100 utilizes a traditional 19-inch front and 16-inch rear wheel configuration. For handling stability, maintain the following pressures:
- Front (100/90-19): 2.1 bar (30 psi)
- Rear (130/90-16): 2.5 bar (36 psi) for solo riders, increasing to 2.8 bar (40 psi) when carrying a passenger.
Electrical and Ignition
The ignition system is optimized for HD 6R12 spark plugs. Ensure the gap is set to factory specifications to prevent fouling. The electrical system is powered by a 65991-82B battery, which provides the necessary cold cranking amps to turn over the high-compression V-twin.
Frequently Asked Questions
Is the XLH-1100 engine different from the 1200?
Yes. While they share the same Evolution architecture, the 1100 has a slightly smaller bore. Many parts are interchangeable, but cylinder and piston sizes are specific to the 1986-87 production run.
Can I use synthetic oil in the XLH-1100?
While modern synthetics are high-quality, the seals in the 1986-87 models were designed for mineral-based HD 360. If switching to synthetic, monitor for any gasket seepage.