1979 Honda CB 650

Make Model	Honda CB 650
Year	1979
Engine	Four stroke, transverse four cylinder, SOHC, 2 valves per cylinder.
Capacity	626.8 cc / 38.2 cu-in
Bore x Stroke	59.8 x 55.8 mm
Cooling System	Air cooled.
Compression Ratio	9.0:1
Induction	4x 26mm Keihin carburetors
Ignition	Transistorized
Starting	Electric
Max Power	63 hp / 46.9 kW @ 9000 rpm
Max Torque	51.5 Nm / 38 ft-lb @ 8000 rpm
Transmission	5 Speed
Final Drive	Chain
Front Suspension	Centre axle coil spring forks
Front Wheel Travel	135 mm / 5.3 in
Rear Suspension	Dual Showa dampers. adjustable spring preload.
Rear Wheel Travel	91 mm / 3.5 in
Front Brakes	Single 275mm disc, 1 piston caliper
Rear Brakes	180mm Drum
Front Tyre	3.50-19
Rear Tyre	4.50-17
Wet Weight	212 kg / 467.3 lbs
Fuel Capacity	18 Litres / 4.7 US gal
Consumption Average	41.1 mpg
Standing ¼ Mile	13.4 sec / 157.7 km/h
Top Speed	190 km/h

The year is 1978, model-year 1979, and Honda eliminates their Single OverHead-Cam Four-Cylinder (SOHC/4) CB550 and CB750 streetbikes from their offerings. Since 1969 Honda's SOHC/4 design had captured the hearts and minds of critic and consumer alike. Beginning with the Harley-killing CB750, Honda's reign on this engine technology would last until 1982, the year the Nighthawk moniker is introduced as the CB650SC. The 1979 CB550 and CB750 grow up and get themselves, among other things, a second camshaft.

The SOHC/4 replacement is the CB650, which, to some, seems little more than a cubic-centimeter compromise. To others, it's a last gasp at an engine technology that, approaching the early 80's, is quickly bound for antiquity in the high-horsepower attitude of the late-70's/early-80's streetbike market. For many owners, these bikes are examples of the perfect middle-weight pocket-rocket. In any event, the SOHC/4 CB650's are truly the culmination of Honda's decade of experience with their ground-breaking SOHC/4 design. ...

"Although the CB650 pulls well from 6000 rpm on, the definite powerband lies between 7500 rpm and redline at 9500."

"There is a clue to emphasis on engine breathing in the CB650's pistons, and combustion chamber shape. The chambers are open and spherical section in form, without funny pockets or ledges. The pistons are domed, but in a very particular way, curving in to follow the shape of the chamber and then going completely flat on top. It's the layout you use when you want the best breathing at any given compression ratio."

"The CB650's vastly improved quarter mile performance has to be a function of real, ex-dyno room, horsepower. The sheer power has to be there, it is there, and it puts the Honda CB650 securely at the top of the list of middleweight contenders. Kawasaki's KZ650, twin overhead camshafts and all, is no performance match for Honda's born-again Four."

"You can work the CB650 right out to the squirming stage of tire adhesion without banging bits of hardware on the road, but it can't be said that the bike encourages such lurid behavior. Neither for that matter does it do anything to actively discourage excessively brisk cornering. It's steady in corners, but not especially solid. What we mean is, the CB650 will arc around turns as steady as its rider; it doesn't have the solid stability that compensates for a little unsteadiness at the controls. If you twitch , it twitches...and does a bit of amplifying just to let you know you should change your ways."

"The CB650 misses being truly new because it was designed to be produced on the old CB550 assembly line, using essentially the same tooling. Honda's decision to build a new motorcycle with existing tooling meant, for example, that the CB650 could have a new cylinder block casting...but its bores and stud holes would have to be on the same centers as those in the earlier model. The decision may have cramped the Honda engineers' usually free-swinging style, but it also meant that the CB650 could be sent to market with a major chunk of its delivery price prepaid."

"Smooth shifting is not the CB650's forte. Shift action is notchy, especially in the first two changes, and we occasionally missed shifts. Although the lever requires only a moderate amount of pressure to shift, changes must be made deliberately; an inattentive flick of the foot won't do."