Japanese Big Four

The Japanese Big Four are the large motorcycle manufacturing companies of Japan: Honda, Suzuki, Kawasaki and Yamaha.

References

• Tony Pashley (2008), How to Build Motorcycle-engined Racing Cars, Veloce Publishing, p. 11, ISBN 9781845841232, Competitive engines are manufactured by the big four Japanese companies: Honda, Kawasaki, Suzuki, and Yamaha. 
• "Harley talks to Big Four, Looks to Triumph", Cycle World 23 (1), January 1984: 24, The enactment of the import tariff ... hasn't kept the two sides -- Harley-Davidson and Japan's Big Four manufacturers--from talking to each other... [Harley has] met with representatives of Honda, Yamaha, Suzuki and Kawasaki to discuss possible alternatives to the tariff.