Pre-war
| Model | Engine | Years | Notes |
|---|---|---|---|
| Models 0, 1 (Named retroactively in 1908) | 24.74 cu in (405.4 cc) IOE single | 1904–1905 | Single-downtube bicycle-like frame, direct leather belt drive, rear coaster brake. Construction began in 1903; sold as production models in 1904–1905 |
| Models 2, 3 (Named retroactively in 1908) | 26.8 cu in (439 cc) IOE single | 1906–1907 | Featured a dual-spring front-end suspension. |
| Model 4 | 26.8 cu in (439 cc) IOE single | 1908 | Larger front fork, tires, and fenders. |
| Models 5, 6 | 30.16 cu in (494.2 cc) IOE single | 1909–1910 | Models 5 and 5A had 28-inch (71 cm) wheels, the former with battery ignition and the latter with magneto ignition. 5B and 5C models offered the same choice of ignitions, with 26-inch (66 cm) wheels for shorter riders. Model 6 series added an idler arm. |
| Model 7D | 49 cu in (800 cc) 45° IOE V-twin | 1911 | |
| Models X8D, X8E | 60.32 cu in (988.5 cc) 45° IOE V-twin | 1912 | "X" model name designated rear-wheel clutch. "D" indicated belt drive; "E" introduced chain drive for the first time. The frame was redesigned to be lower-slung and had a spring suspension in the rear downtube. |
| Models 9A, 9B | 34.47 cu in (564.9 cc) IOE single | 1913 | Model 9A was belt-drive-equipped; 9B, chain-drive. The updated single-cylinder motor used a mechanical intake valve, like that first introduced on the V-twin model. |
| Model 10F | 49.48 cu in (810.8 cc) 45° IOE V-twin | 1914 | The two-speed transmission was introduced and showcased on this model, along with a step-starter, enclosed intake valve, a primary chain drive, and optional sidecar. |
| Model 11F | 61 cu in (1,000 cc) 45° IOE V-twin | 1915 | Three-speed transmission and electric head- and taillights debuted on this model. |
Read more about this topic: List Of Harley-Davidson Motorcycles