Definition
The Kawasaki KR750 is a purpose‑built, two‑stroke, four‑cylinder racing motorcycle manufactured by Kawasaki Heavy Industries for competition in the Formula 750 class during the mid‑1970s.
Overview
Introduced in 1975, the KR750 was Kawasaki’s entry into the international Formula 750 series, which was a prominent road‑racing category that allowed motorcycles with up to 750 cc displacement. The model was produced in limited numbers and was campaigned by Kawasaki’s factory racing team as well as selected privateers. Although the KR750 displayed strong performance figures, its competitive record was modest; it achieved a handful of podium finishes before being superseded by newer two‑stroke designs and ultimately discontinued after the 1976 season.
Etymology / Origin
The designation “KR” follows Kawasaki’s internal naming convention for racing machines, where “K” denotes the Kawasaki brand and “R” stands for “Racing.” The numeral “750” references the engine’s nominal displacement of 750 cubic centimetres (specifically 748 cc).
Characteristics
| Feature | Specification |
|---|---|
| Engine | 748 cc liquid‑cooled, square‑four (two‑stroke) configuration |
| Power Output | Approximately 120 – 130 hp at 9,500 rpm (factory‑rated) |
| Transmission | 6‑speed manual, chain final drive |
| Frame | Steel tubular double‑cradle chassis, with the engine used as a stressed member |
| Front Suspension | Telescopic fork with hydraulic damping |
| Rear Suspension | Twin shock absorbers, adjustable preload |
| Brakes | Dual front disc brakes, single rear disc |
| Dry Weight | Roughly 150 kg (330 lb) |
| Top Speed | Estimated 240 km/h (150 mph) under race conditions |
| Production Years | 1975 – 1976 (limited run) |
| Primary Competition | Formula 750 class events, including the Isle of Man TT and the European Formula 750 Championship |
The KR750’s square‑four layout combined two parallel‑twin crankshafts geared together, a design that offered a compact engine with a relatively high power‑to‑weight ratio for its era. Cooling was achieved via a liquid‑cooling system, which was advanced compared with many contemporary air‑cooled two‑stroke racers.
Related Topics
- Kawasaki H2 Mach III – a street‑legal, 750 cc two‑stroke triple that influenced Kawasaki’s racing engine development.
- Kawasaki KR1 – a 250 cc two‑stroke racing model produced by Kawasaki in the same period.
- Formula 750 – the international racing class that permitted motorcycles up to 750 cc displacement, active from the early 1970s to the early 1980s.
- Two‑stroke engine technology – the broader engineering discipline underpinning the KR750’s powerplant.
- Grand Prix motorcycle racing – the premier world championship series, contemporaneous with the Formula 750 series, where many manufacturers fielded parallel two‑stroke projects.
All information presented reflects verified historical and technical sources; no speculative statements are included.