Honda CB750K/reviews

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Honda CB750K4[edit]

It is no exaggeration to say the Honda CB750 is the most significant motorcycle ever made and altered the world of motorcycling forever. Prior to the CB750 you had two choices in motorcycles: You could have a small, reliable Japanese bike or you could have a larger, faster but unreliable bike. The CB750 proved to the doubters that the Japanese could build a large bike (a 750 was considered monster-size in those days.) It was the first to come standard with a hydraulic disk brake. It had both electric and kick start. It started every time, parts didn't fall off and it didn't leak oil. We take these things for granted today but it really meant something in 1970!

It wasn't all about practical everyday driving either. The CB750 was equally at home on the racetrack. A modified CB750 won the 1970 Daytona and set a new track record. The world took notice.

The British motorcycle industry, notorious for unreliable motorcycles and already on the ropes, was finally put out of their misery. This bike and its successors very nearly put Harley-Davidson out of business too. The CB750 raised the bar in the industry. You had to either improve your designs or get out of the motorcycle business.

Honda built about a million of the CB750s over its ten year history. To get a feel for how popular that is consider that BMW, which has been making motorcycles far longer than Honda, only recently rolled its millionth bike off the assembly line.

I was only five years old when the CB750 first appeared so I was too young to understand its importance. The CB750 was a common "college" bike when I was in school. They were reliable, plentiful and cheap. You could keep those bikes going forever. I bought this bike to relive those times and see if a twenty-seven year old bike could still compare to a modern machine.

My 1974 CB750 came from a collector who had partially restored it. It is in excellent mechanical condition, very good cosmetic condition and the mileage is low (13,000 miles when purchased.) It's a good candidate to compare to modern motorcycles. My girlfriend has named her "Pumpkin" for her bright orange color.

On to the good stuff. How is it to ride? The short answer is it is still fun to ride today. No, Pumpkin can't match modern motorcycles in many ways but the differences are not annoying and there is a certain special satisfaction when riding a bike that is a part of history.

The differences become pronounced once you start to push the bike and feel around the edges. The CB750 is much heavier than modern bikes and perhaps more important it carries its weight high. You have to keep this in mind when corning at speed but it generally doesn't get in the way. The single disk brake with its one piston caliper was the marvel of its day but pales in insignificance compared to something like the antilock power brakes on my BMW R1150RT. The right attitude for any bike of this vintage is to think of the brakes as something that slow you down rather than stop you.

Acceleration is quick and torque is adequate at high revs as you would expect in an inline four. She can keep up with modern sport bikes in the straights although the handling is inferior in the curves.

The engine takes a few minutes to warm up before it's happy. This is still true today with modern inline fours but computer controlled ignition and fuel injection take all the fun out of it. You have to adjust the idle level and there never really is anything like keeping it spot on. After riding at high speed for several minutes the engine reaches its maximum normal operating temperature and you will notice the idle creeping up to 2,000 rpm. Just live with it or get used to reaching behind the carbs and adjusting the idle screw with your left hand. Careful not to burn yourself!

The petcock is oddly on the right side of the frame. What happens when you're riding and have to switch to reserve? The only safe thing to do is pull over to turn the petcock.

But these are nothing more than little quirks that give the bike its character. Pumpkin is still every bit as competent a street bike as she was in 1974 and none of the pleasure has faded.

There is a reassuring feeling about having the kickstart on the bike. Honda felt that customers weren't ready to trust an electric starter so they included one. Pumpkin starts on the first or second kick when warm. I haven't tried to kickstart her when cold.

I'm glad to have her. Despite her age she still puts a smile on my face and that is, after all, the final test.

Make Model Honda CB 750 Four K4
Year 1974
Engine Type Four stroke, transverse four cylinder, SOHC, 2 valve per cylinder.
Displacement 736 cc / 44.9 cub in.
Bore X Stroke 61 х 63 mm
Compression 9.0:1
Cooling System Air cooled
Lubrication Dry sump
Induction 4 x 28 mm Keihin carburetors
Ignition Battery, ignition coil
Spark Plug NGK D8ES-L, NDX 24 ES
Starting Electric, kick
Max Power 50 kW / 67 hp @ 8000 rpm
Max Torque 44 lb-ft / 60 Nm @ 7000 rpm
Clutch Multi-plate, wet
Transmission 5 Speed
Final Drive Chain
Gear Ratios 1st 13.99 / 2nd 9.54 / 3rd 7.45 / 4th 6.14 / 5th 5.26:1
Frame Tubular steel duplex cradle
Front Suspension Telescopic forks non adjustable.
Front Wheel Travel 143 mm / 5.6 in.
Rear Suspension Swingarm, dual shocks, preload adjustable.
Rear Wheel Travel 85 mm / 3.3 in.
Front Brake Single 296 mm disc
Rear Brake 179 mm Drum
Front Tire 3.25-19
Rear Tire 4.00-18
Rake 27°
Trail 95 mm / 3.7 in
Dimensions Length: 2175 mm / 85.6 in. Width: 870 mm / 34.3 in. Height: 1170 mm / 46.1 in.
Wheelbase 1453 mm / 57.2 in.
Seat Height 810 mm / 31.9 in.
Ground Clearance 140 mm / 5.5 in.
Wet Weight 218 kg / 479 lbs
Fuel Capacity 17 L / 4.5 US gal
Reserve 5 L / 1.3 US gal
Oil Capacity 3.5 L / 3.7 US quarts
Consumption Average 6.9 L/100 km / 14.6 km/l / 34.3 US mpg
Braking Distance 48 Km/h / 30 Mph - 0 10 m / 32.9 ft
Braking Distance 97 Km/h / 60 Mph - 0 41 m / 135.7 ft
Standing ¼ Mile 13.5 sec / 100.9 mph
Top Speed 198 km/h / 123.2 mph
Colours Flake sunrise orange, Freedom green metallic, or Boss maroon metallic