.

Honda CB750A Hondamatic

.  

Make Model

Honda CB750A Hondamatic

Year

1977

Engine

Four stroke, transverse four cylinder, SOHC, 2 valve per cylinder.

Capacity

736 cc / 44.9 cu-in
Bore x Stroke 61 х 63 mm
Cooling System Air cooled
Compression Ratio 9.2:1

Induction

4x 28mm keihin carburetors

Ignition 

Battery induction coil
Starting Electric

Max Power

50 kW / 67 hp @ 8000 rpm

Max Torque

44 lb-ft / 60 Nm @ 7000 rpm

Transmission 

2 Speed 
Final Drive Chain
Frame Painted steel

Front Suspension

Telehydraulic forks

Rear Suspension

Swingarm with dual shocks.

Front Brakes

Single 296mm disc

Rear Brakes

Single 296mm disc

Front Tyre

3.25-19

Rear Tyre

4.00-18
Rake  62.5°
Trail 115 mm / 4.5 in
Wheelbase 1480 mm / 58.3 in

Dry Weight

245 kg / 540.1 lbs

Fuel Capacity 

19.5 Litres /

Consumption Average

15.6 km;/lit

Standing ¼ Mile  

15.8 sec

Top Speed

158 km/h

The part of riding a motorcycle that newcomers typically find most difficult is balancing clutch and throttle control when taking off from a standstill. So a motorcycle without a clutch should be a no-brainer — shouldn’t it?

That’s presumably what Honda thought when they brought the Honda CB750A Hondamatic to market in 1976. Superficially, the A model can be thought of as a Honda CB750F with a torque converter and two-speed transmission instead of the regular bike’s five-speed cog box. In practice, though, the 736cc inline four got pretty much a complete makeover.

Revisions to the combustion chambers lowered compression, which, with smaller carbs, camshaft changes and a four-into-one exhaust revised the power curve for more low-down thrust to suit the characteristics of the torque converter. An accelerator pump fitted to the number two carburetor (but feeding all four) helped to alleviate a known flat spot off idle in the standard power delivery of the Honda CB750F. A new Hy-Vo chain drove a jackshaft behind the crank, and powered the torque converter’s oil pump, with gear drive to the two-speed tranny. To provide an oil bath for the transmission and torque converter, the engine’s lubrication was switched from dry to wet sump.

Just two speeds? With the torque converter doing the hard work, that’s all Honda’s suits decided it needed. But while the torque converter replaced the clutch, shifting between the two gears was done manually with a conventional foot pedal. The reason? Honda figured an unexpected shift mid-turn might alarm an inexperienced rider — arguably their target demographic. In any case, the Honda CB750A would comfortably pull away from a standstill in high gear (“drive”): it just did it more quickly in “low.”

.  

For the engine to turn when the starter was pressed, the transmission had to be in neutral. And if you forgot to shift into neutral before parking the Honda CB750A, deploying the side stand would do it for you. Both of these features were obviously intended to prevent unintended launches. Similarly, a push-button parking brake acting on the rear wheel prevented the bike from rolling away if parked on a slope, there being no direct gear linkage between engine and wheels. Even after the brake button was released, the brake remained on and the bike wouldn’t roll until the rider dabbed the brake pedal.

Instruments were also different on the Honda CB750A Hondamatic. No tachometer was fitted, although the speedometer showed the maximum speeds in low and drive, 60 and 105mph, respectively. Idiot lights indicated low, drive and neutral, as well as more usual functions like oil pressure, high beam and turn indicators.

Model History

The CB750A Hondamatic 750 was sold in 1975 in Canada -- one year before it was offered in the USA. It was available in one of two colors: Muscat Green Metallic or Candy Antares Red. The exhaust system was a 4-into-1. The bike had wire spoke wheels with aluminum rims. The transmission was a 2-speed with a fluid torque converter. The engine was a 736cc SOHC 2-valve air-cooled inline 4 cylinder with a chain drive. The serial number began CB750A-6000001.

The CB750A'76 Hondamatic 750 was introduced into the USA in 1976 but the Hondamatic had been sold in Canada in 1975. It was available in one of two colors: Muscat Green Metallic or Candy Antares Red. The exhaust system was a 4-into-1. The bike had wire spoke wheels with aluminum rims. The transmission was a 2- speed with a fluid torque converter. The engine was a 736cc SOHC 2-valve air-cooled inline 4 cylinder with a chain drive. The serial number began CB750A-7000001.

The CB750A'77 Hondamatic 750 was sold in 1977 in one of two colors: Candy Sword Blue or Candy Presto Red. The exhaust was now a 4-into-2. The gas tank and side covers had gold pinstripes. The bike had wire spoke wheels with aluminum rims. The transmission was a 2-speed with a fluid torque converter. The engine was a 736cc SOHC 2-valve air-cooled inline 4 cylinder with a chain drive. The serial number began CB750A-7100001.

The CB750A'78 Hondamatic 750 was sold in 1978 in one of two colors: Candy Alpha Red or Candy Polaris Blue. The bike had comstar wheels. The gas tank and side covers had gold pinstripes. The exhaust was a 4-into-2. The transmission was a 2-speed with a fluid torque converter. The engine was a 736cc SOHC 2-valve air-cooled inline 4 cylinder with a chain drive. The serial number began CB750A-7200001.