The Hondamatic 450’s top speed was about 100 mph (roughly 160 km/h) in ideal conditions.
The Hondamatic 450 refers to Honda’s CB450 model equipped with the Hondamatic automatic transmission—a rare version produced in the late 1960s. Because the bike used a torque-converter automatic with added weight and different gearing, its top speed tended to be slightly lower than the manual-transmission CB450, with real-world results varying by year, maintenance, rider weight, and wind.
What is the Hondamatic 450?
The CB450 Hondamatic was Honda’s foray into automatic motorcycles, pairing a 447cc parallel-twin engine with a two-speed automatic transmission driven by a hydraulic torque converter. It represented an early attempt to offer ease of use without requiring clutch operation, trading some performance for simplicity.
Mechanical setup
In this configuration, the motorcycle used a hydraulic torque converter to handle forward motion and a simplified gear set that shifted automatically. Riders did not use a traditional clutch lever, and the bike offered Drive and Low settings rather than a fully manual gearbox.
Performance and top speed
Top speed figures are approximate because they depend on wind, rider weight, maintenance, tires, and other conditions. Historical testers and enthusiasts generally place the CB450 Hondamatic in the high-90s mph range, with many reports citing around 95–100 mph (about 153–161 km/h) in optimal conditions.
Factors that affected speed
Several variables influenced final performance, including aerodynamics, engine tune and fuel delivery, transmission condition, tire quality, and the extra weight of the automatic system compared with the manual CB450.
Historical context and legacy
Introduced during Honda’s experimentation with automatic transmissions, the Hondamatic 450 remains a niche collector’s item today. While rare, it is remembered for offering a smoother, clutch-free ride and for illustrating how automatics could be adapted to motorcycles in that era.
Preservation and restoration
Today, surviving Hondamatic 450s require careful restoration to address the unique transmission components. Parts can be scarce, and specialists with knowledge of the Hondamatic system are essential for proper maintenance.
Summary
The Hondamatic 450—known as the CB450 Hondamatic—delivered top speeds around 95–100 mph under favorable conditions, reflecting the compromises of an automatic transmission. Its significance lies in its place in motorcycle history as an early experiment with automatics, offering user-friendly operation at the expense of peak performance. For collectors, it remains a distinctive relic of Honda’s late-1960s engineering efforts.