CB750 K8: 1978
| Production Dates | May 1977 through May 1978 |
|---|---|
| Production Numbers | 36,000 |
| US Serial Numbers | Frame: 3000001 – 3062980 Engine: 2800001 – 2862980 |
| Canada Serial Numbers | Frame: 3001934 – 3061938 Engine: 2801946 – 2861935 |
| Colors | Candy Alpha Red, Excel Black |
| Features | The gas tank stripe was gold with a gold and red pinstripe. The “750 FOUR” side cover emblem was a graphic design. There was a “K” side cover decal and stripe. The seat is contoured in a stepped design. |
| Dimensions | ||
|---|---|---|
| Item | English | Metric |
| Overall length | 89.8 in. | 2,280 mm |
| Overall width | 34.6 in. | 880 mm |
| Overall height | 46.7 in. | 1,185 mm |
| Wheel base | 58.9 in | 1,495 mm |
| Seat height | 31.9 in. | 810 mm |
| Foot Peg Height | 13.0 in. | 330 mm |
| Ground Clearance | 5.9 in. | 150 mm |
| Curb weight (dry) | 508 lb | 231 kg |
| Frame & Suspension | ||
|---|---|---|
| Type | Double cradle | |
| Front Suspension | Telescopic fork, travel 5.6 in., 141.5mm | |
| Rear Suspension | Swing arm, travel 4.0 in., 101.6mm | |
| Front Tire Size, Type | 3.50H-19 (4PR) Rib, tire air pressure 2.0 kg/cm2, 28 psi | |
| Rear Tire Size, Type | 4.50H-17A (4 PR) Block, tire air pressure 2.25/2.8 kg/cm2, 32/40 psi | |
| Front Brake | Disk brake | |
| Rear Brake | Internal expanding shoe | |
| Fuel Capacity | 5.1 US gal, 4.3 Imp. gal | 19.5 liter |
| Fuel Reserve Capacity | 1.1 US gal, 0.9 Imp. gal | 4.0 liter |
| Caster Angle | 62º | |
| Trail Length | 4.5 in. | 115 mm |
| Front fork oil capacity (refill) | 5.3-5.4 ozs | 145-155cc |
| Engine | ||
|---|---|---|
| Item | English | Metric |
| Type | Air-cooled, 4-stroke, O.H.C. engine | |
| Cylinder Arrangement | 4-cylinder in line | |
| Bore and Stroke | 2.402x2.408 in. | 61.0x63.0 mm |
| Displacement | 44.9 cu in | 736 cc |
| Compression Ratio | 9.2:1 | |
| Carburetor | Four piston valve type, venturi diameter 28mm (1.102in) | |
| Valve train | Chain driven over head camshaft | |
| Oil Capacity | 3.7 US qt, 3.1 Imp. pt | 3.5 liter |
| Lubrication System | Forced pressure and dry sump | |
| Fuel Required | Low-lead gasoline with 91 octane number or higher | |
| Air Filtration | Paper filter | |
| Intake Valve | Opens: 0 degrees BTDC, Closes 40 degrees ATDC | |
| Exhaust Valve | Opens: 40 degrees BBDC, Closes 0 degrees ATDC | |
| Valve Tappet Clearance | Intake: 0.002in./0.05mm | Exhaust: 0.003in./0.08mm |
| Pilot Screw Opening | Fixed by idle limiter (1 1/2 +/- 1/2) | |
| Idle speed | 1000 rpm | |
| Drive Train | ||
|---|---|---|
| Clutch | Wet, multi plate type | |
| Transmission | 5-speed, constant mesh | |
| Primary reduction | 1.708 | |
| Gear ratio I | 2.500 | |
| Gear ratio II | 1.708 | |
| Gear ratio III | 1.333 | |
| Gear ratio IV | 1.133 | |
| Gear ratio V | ||
| Final Reduction | 2.733, drive sprocket 15T, driven sprocket 41T | |
| Gear shift pattern | Left foot operated return system | |
| Electrical | ||
|---|---|---|
| Ignition | Battery and ignition coil | |
| Ignition Advance | "F" mark: 10 degrees BTDC; Max Advance: 35 degrees; RPM from "F" to Max: 1,200-2,500; Dwell angle: 190 +/- 5 degrees | |
| Starting system | Electrical motor or kick pedal | |
| Alternator | Three phase A.C. generator 0.21kW@5,000 rpm | |
| Battery Capacity | 12V - 14AH | |
| Fuse Capacity | Main: 15A; Head: 7A; Tail: 5A | |
| Spark plug | USA: NGK D8EA, ND X24ES-U Canada: NGK DR8ES-L ND X24ESR-U | |
| Condenser Capacity | 0.20-0.24mf | |