CB400F

Welcome to CB400F.webs.com. 

For owners & fans of the Honda CB400F Super sport 1975-1978.

Intro

 In 1969 Honda released the CB750, although it was neither the first four cylinder motorcycle or have the largest capacity, it certainly left it's mark as the number one super bike. I read somewhere that, the if first Japanese bikes sent the message to Britain, "watch out we're coming", the CB750 delivered the message "it's too late we're here". By the mid 70s there was little left of the once great British motorcycle industry.  

 Fitted with a hydraulic front disc brake, electric start & indicators as standard the CB750 paved the way for years to come. In 1971 Honda had introduced a scaled down version,the CB500 followed by the CB350F in 1972. The CB350F was introduced in the US but it never really caught on, and was dropped from production in 1974. The CB350F was not marketed in the UK.

 Enter the CB400F

 The CB400F (aka  the 400/4 or 400 four super sport), was unveiled for 1975. It was an instant hit, a compact bike developed from, and improved on the previous CB350F, with uprated performance via an increased bore from 47mm to 51mm, bringing capacity up to 408cc, larger valves, and a six speed gearbox, it had updated styling with a neat offset chrome 4 into 1 exhaust system, a flatter angular fuel tank & flat side panels with transfers instead of badges, low handle bars, slightly rear set footrests and a studded seat, 

 The bike had a sporty cafe racer look and feel, ride and handling were deemed excellent at the time. All this brought together a universal bike which was easy, exiting and smooth to ride in various situations, giving you a feeling of control, riding in harmony with a thoroughbred. The press loved it.

Models 

 For the European/UK market first there was the F available from 1975 in Light ruby red or Varnish blue, early F models up to frame number 1056883 had the pillion foot rests mounted on the rear swinging arm, (pillion assisted suspension! )  later F models which ran to frame number 1073399 had them mounted to the frame.

 In 1977 the F2 was available in Parakeet yellow or Candy antares red (metallic). These also had striping to the tank. and solid lettering with an outline to the side panels. F2 models ran frame number 1073400.

 "Just in case you were wondering Antares is a red super giant star, & a parakeet is a large type of budgie, maybe Honda intended the red one for the touring & the yellow one for flying to the cafe"

 There was also a F1 in 1976 model which was not marketed in the UK or Europe, these were finished in Light ruby red or Parakeet yellow & had black side panels. 

 Racing

 Not long after the 400/4 hit the road, it was regularly appearing on the race track. Kazuo Yoshima heavily modified the CB400F. On the track he regularly finished ahead of CB750s & Kawasaki Z1s. There were many aftermarket parts available such as the Yoshimura big bore kit & modified camshafts. Other companies offered performance exhausts, electronic ignition, uprated shocks & brakes, as well as cafe style seats & drop bars. 

 Living with it

 The 400 four is equipped with a side stand and a center stand which is handy for maintenance. It also has an electric start & a kick start, you have to flip up the right foot rest to use the kick start. This is handy if the battery is low, as the starter robs the voltage to the ignition coils. It's a easy to start this way, as easy kicking up any 125, it bursts into life without any effort, no messing about tickling carbs, cranking over 3.5 times, finding compression, praying etc.

 After starting the bike from cold, it needs to warm up on part choke for a few minutes before setting off, or you could find yourself fumbling with the choke whilst riding. 

 Although it does pull well from the start, the engine is high revving, giving peak power of 37bhp at 8,500rpm, with a redline at 10,000rpm, & with 6 gears to choose from you'll find your left foot is kept busy if you want to make the most of it. It accelerates well from 0-70mph, steadily from 70-90mph and eventually from 90 onwards. The Seating position is slightly bent forward, giving a dominant street fighter feel, which is well balanced at normal speeds, but at high speeds above 80mph, you get the urge to crouch over the tank and reduce the wind drag.

 The bike handles very well at all speeds giving good cornering and a comfortable ride, the rear can feel a little skittish sometimes depending on the road condition.

  End of the road

 The 400 four was dropped from production at the end of 1977 due to the high cost of manufacture & competition from it's less costly Japanese rivals, the Yamaha RD400, the Suzuki GT380, the Kawasaki KH400 & the Kawasaki Z400. The reason that it cost more to build was probably due to the complexity of the engine, which had 4 cylinders, 4 carbs & it was a four stroke so needed 8 valves a camshaft and cam chain, as opposed to the competition's 2 & 3 cylinder two strokes, & the Z400's 2 cylinder 4 stroke. 

 In 1978 Honda introduced the CB250N & CB400N Superdream twins, leaving CB400N (U.S.400 Hawk) to fill the void left by the CB400F.

Engine 

Type                       SOHC 4 cylinder 4 stroke 

Bore x stroke          51 x 50mm

Capacity                 408cc

Compression          9.4:1

Lubication              Wet sump

Carburation            4x 20mm Keihin

Bhp at rpm             [email protected] 8,500 rpm

Max torque             24ft/lbs @ 7,500 rmp

Gearbox                 6 Speed

Clutch                     Wet multi-plate

Starting                  Electric & kick

Charging Output:    156w
Battery                    12v 12AH 

PERFORMANCE
Top Speed              95 mph - 103mph (crouched down, arms & legs tucked in)
0-60:                        6.70 seconds
Standing 1/4:          14.71 sec @ 86.04 mph
RPM @ 60mph        5465

Fuel consumption   49.7 mpg overall 42 mpg ridden hard

Chassis

Wheelbase              53.30 in  1355mm

Seat Height             31.10 in  790mm

Ground clearance   6 in        150mm

Kerb weight            392 lbs    178kg

Fuel capacity          3.1 imp gals  14ltr

Front Tyre               3.00S-18

Rear Tyre                3.50S-18

Front Brake            Single 10.25in disc

Rear Brakes            6.3 x 1.2"drum

Front Suspension    Telescopic fork

Rear Suspension     Swing arm, adjustable hydraulic shocks

Instrumentation       Speedometer with trip, Tachometer, Oil lamp, Neutral lamp