With the appearance of the Japanese brands on the motorcycle market at the end of the 60s, a race of performance and technology started between different bike manufacturers. The first battle was about power and the aim of creating high cc bikes at the end of the 60s/beginning of the 70s, such as the CB750 and Z1. The end of the 70s saw a rise in awareness of emissions, which pushed manufacturers to create more environment-friendly bikes. Honda, which in motorcycle history has always been one of the most innovative and advanced manufacturers, released the CX500 in 1978 with the objective of introducing a mid-size engine bike with low emissions and low maintenance. While the bike succeeded in that objective, the thrill and the speed were kind of lost. Just like 10 years before with the CB750, Honda wondered how they could innovate, and what they could do or create to keep the efficiency of the CX while adding some spice. In 1982, the Japanese manufacturer releases the CX500TC, a CX500 equipped with a turbo. That first shot was good but not satisfying due to “turbo lag” and difficulty to handle the bike when turbo starts working. One year later, Honda tried to fix these issues releasing the CX650 Turbo.
The 500cc engine equipped the CX was re-bored to 674cc, the compression ratio increased from 7.2:1 to 7.8:1, and the gear ratios for 4th and 5th were adjusted as well. All of these modifications helped to keep boost engaged, a clever and lightweight way to increase motorcycle power at high rpms using the motorcycle’s own exhaust gases to activate it. To make a long story short, the turbo is plugged to the exhaust system and the first rotor is activated by the exhaust gases. A second rotor is activated by the first rotor when it starts working. That second rotor sends compressed air to the intake manifold which creates a denser air charge and larger fuel/air charge, therefore increasing power. The CX650 Turbo developed 100hp to move a wet weight of 573 pounds, permitting the bike to reach a crazy top speed of 140 mph. For more information about the CX650 turbo, please check out this article on Motorcycle Classics.
The bike presented here is in good shape and seems to be mostly original. The original paint and original exhaust are still in very good condition. The seat is a brand-new replica of the original one. The seller indicates that he just bought the bike from the first owner and only 12k miles have been put on it. He also claims that all the fluids have been changed. Two videos have been made of the bike, one to see the aesthetic condition of the bike:
The second video is to appreciate the engine and a startup:
Find this Honda CX650 Turbo in San Diego, California with bidding up to $4,600