The air/oil cooled DOHC 902 cc (55.0 cu in) engine has 4 32 mm Keihin CV carburetors and electronic ignition.

[1] The GL and CX series of touring motorcycles of the time are the source of the final drive and rear suspension assemblies of the CB900C.

The sub-transmission involves a jack shaft that allows the rider to select a "high" or "low" range for the five gears,[3] effectively giving an overdrive 6th speed for cruising.

The Rider and Cycle World reviews of 1980 were less than enthusiastic, complaining of "a lack of purity in the custom styling".

Despite the lacklustre reviews, the CB900 Custom has gained a small cult following due to its 10 speeds, styling, comfort, reliability, and ample power output.