Honda CB550K Four
Honda CB550K Four | |
Manufacturer | |
---|---|
Production | 1976 - 78 |
Class | Standard |
Engine | Four stroke, transverse four cylinder, four stroke, SOHC, 2 valves per cylinder. |
Compression ratio | 9.0:1 |
Ignition | Battery, with points |
Transmission | 5 Speed |
Frame | Double cradle tubular steal |
Suspension | Front: 35mm Telescopic hydraulic forks, Rear: Dual shocks, lateral adjustable preload |
Brakes | Front: Single 270mm disc Rear: Drum |
Front Tire | 3.25-19 |
Rear Tire | 3.75-18 |
Wheelbase | 1405 mm / 55.3 in |
Seat Height | 805 mm / 31.7 in |
Weight | 191 kg / 421 lbs (dry), 206.0 kg / 454.2 lbs (wet) |
Recommended Oil | Honda GN4 10W-40 |
Fuel Capacity | 16 Liters / 4.2 US gal |
Manuals | Service Manual |
Engine[edit | edit source]
The engine was a Air cooled cooled Four stroke, transverse four cylinder, four stroke, SOHC, 2 valves per cylinder.. The engine featured a 9.0:1 compression ratio.
Chassis[edit | edit source]
It came with a 3.25-19 front tire and a 3.75-18 rear tire. Stopping was achieved via Single 270mm disc in the front and a Drum in the rear. The front suspension was a 35mm Telescopic hydraulic forks, while the rear was equipped with a Dual shocks, lateral adjustable preload. The CB550K Four was fitted with a 16 Liters / 4.2 US gal fuel tank. The bike weighed just 191 kg / 421 lbs. The wheelbase was 1405 mm / 55.3 in long.
Photos[edit | edit source]
Overview[edit | edit source]
Honda CB 550K Four
Honda CB550 History
The Honda CB550 was probably the best balanced Honda of the
seventies. It did not have the awe-inspiring power of the legendary CB750, but
it had a stiffer frame and was a lighter and more nimble motorcycle. We might
describe the Honda CB550 as Hondas Goldilocks bike the CB750 was too big
and powerful for many, the smaller bikes such as the CB360 and CB400 were too
small (and the CB360 was not particularly stable as you got it up into its top
speed range). But the CB550 was just right. The Honda CB550 was introduced in
1974 and remained in production for five short years until 1978.
The CB550 was in some respects a bug fix model descended from
its predecessor the CB500 and made to not only improve on power but to remedy
the technical faults that had dogged the CB500. The engine of the CB550 was the
same power plant as fitted to the CB500 but with its capacity increased to 544cc
(33.2 cu. in.) lifting its power to 50 hp at 8,000rpm with torque of 30.4 lbf.ft
at 7,500rpm. The engine breathed through four 22mm Keihin carburettors in
typical Honda style. The engines compression ratio was 9:1 which means it
preferred the leaded super grade gasoline of the time.
The engine was a typical Honda in-line four cylinder with single
valves (i.e. 8 valves) and a single overhead camshaft. This engine was mounted
transversely in the frame and made as a unit with the five speed transmission.
That five speed transmission remedied the gear change problems of the CB500 and
was nice and crisp to use. The clutch slipping bug of the CB500 was also fixed
in the CB550. As this engine was significantly lighter than that of the CB750
the handling of the CB550 was livelier, and it was a much easier bike to ride.
The frame of the CB550 was a steel cradle type with twin
down-tubes. It was a stiff frame well engineered for the weight and power of the
bike and contributed greatly to the bikes handling. The 35mm front forks were a
telescopic free valve type whilst at the rear were twin shocks with adjustable
pre-load. Brakes of the CB550 were a single caliper single 11 disc at the front
and a drum at the rear. The brakes worked well. The seat was set at a height of
31.7 (805mm) making this a good choice for those of us who are not 6′ plus.
This relatively low seat height combined with the modest weight
(wet weight of 423lb/192kg for the CB550K and slightly less for the Super
Sports CB550F) made this an attractive motorcycle for newer riders as well as
for those looking for a lively and fun road bike. Wheels were 19 x 3.25 front
and 18 x 3.75 rear and the wheelbase was a comfortably long 55.3in./1,405mm.
The fuel tank held 3.7 US gallons (14 liters) and on some later models of the
CB550K and all models of the CB550F featured a filler that lurked under a key
locked flap on top of the tank. It worked well enough and provided some security
but not everyone liked it.
The claimed fuel consumption was between 40-50 miles to the US
gallon. In real world road tests however the CB550 tended to deliver in the low
forty miles to the Imperial gallon and down to 38mpg (Imperial gallons) if
pushed hard. This bike would happily sit on 70mph at a comfortable 6000rpm in
fifth gear and had a top speed north of 90mph with some claiming the bike could
just make the ton (100mph).
For those of us who think that 70mph is a nice comfortable
cruising speed the CB550 would sing along the highway, the rider being aware of
the high frequency buzz of engine noise that would make its way through the
helmet, but the buzz was certainly not accompanied by vibration. On long trips
the seat could leave something to be desired and has been described as being a
bit bum numbing, but there are not a lot of motorcycles that dont fit that
description.
The Honda CB550K
The CB550K was the first of the two models of the CB550 and was
made in the style of the CB750 of the same time. Riding position was sit up and
beg and the exhaust was split as two into one on either side.
The paint scheme changed every year of the bikes production as
follows:
CB550K0 (1974); Flake Sunrise Orange, Boss Maroon Metallic, and
Freedom Green Metallic. The tank color scheme was two tone with a black panel
outlined in gold on the side of the tank.
CB550K1 (1975); Candy Jade Green and Flake Sunrise Orange. The
shape of the black side panel outlined in gold was slimmer. Instrument faces
changed to dark green.
CB550K2 (1976); Candy Garnet Brown. The shape of the black side
panel outlined in gold reverted to the 1974 style which was the same style as on
the CB750. Instrument face color changed to light green.
CB550K3 (1977); Candy Garnet Brown and Excel Black. The fuel
tank side panel painted red with gold outline. Side cover now given a 550 Four
K emblem. This model introduced the fuel filler placed under a locking top
cover flap, sometimes called the bathtub filler. This change was made to suit
the US market.
CB550K4 (1978); Candy Alpha Red and Excel Black. Side cover
given a gold pinstripe. Seat design changed to a dual contour style.
The Honda CB550F
The CB550F is without doubt the nicer of the two models. The
CB550F was the Super Sport model and it was more of a conservative café racer
style without the emphasis on the racer part.
The CB550F featured slightly lower handlebars, rising only about
two inches above the head stock. So the riding position is a little more leaning
forward but comfortable, and perhaps better when you are up at motorway speeds.
The aesthetics of the CB550F are what really sets it apart
however. This bike has minimal chrome, simple plain paintwork on the tank and
side plates, and a four into one exhaust system that manages to look a whole lot
more businesslike than the two either side of the CB550K.
The four into one exhaust system improves the aesthetics of the
bike but its bulk does mean that it is possible to scrape the pipe on the tarmac
if you are cornering at a foot-peg sparking lean. For brisk cornering the CB550F
preferred gear-changing being done before a corner with progressive acceleration
through it. Attempting to enter a corner whilst still braking and changing gear
tended to result in a wiggle in the tail end as a bit of a reminder that the
CB550F is a sporting motorcycle, not a racing motorcycle.
Paint scheme changed each year of production as follows:
CB550F0 (1975); Candy Sapphire Blue and Flake Sunrise Orange.
550 Four decal on side panel. Dark green instrument faces.
CB550F1 (1976); Flake Sapphire Blue and Shiny Orange (note: same
colors as for 1975 but different names). Dark brown seat and light green
instrument faces.
CB550F2 (1977); Candy Sword Blue and Candy Presto Red. Gold tank
stripe with side covers painted plain black. Black seat. Fork boots no longer
used.
Source
Make Model | Honda CB 550K Four |
---|---|
Year | 1976 - 78 |
Engine Type | Four stroke, transverse four cylinder, four stroke, SOHC, 2 valves per cylinder. |
Displacement | 544 cc / 33.1 cu-in |
Bore X Stroke | 58.5 x 50.6 mm |
Cooling System | Air cooled |
Compression | 9.0:1 |
Induction | 4x Keihin, Ø 22 mm carburetors |
Ignition | Battery, with points |
Starting | Electric & kick |
Max Power | 50 hp / 36.5 kW @ 8500 rpm |
Max Torque | 43.1 Nm / 31.8 lb-ft @ 7400 rpm |
Transmission | 5 Speed |
Final Drive | Chain |
Frame | Double cradle tubular steal |
Front Suspension | 35mm Telescopic hydraulic forks, |
Rear Suspension | Dual shocks, lateral adjustable preload |
Front Brakes | Single 270mm disc |
Rear Brakes | Drum |
Front Tire | 3.25-19 |
Rear Tire | 3.75-18 |
Rake | 64° |
Trail | 105 mm / 4.1 ub |
Wheelbase | 1405 mm / 55.3 in |
Seat Height | 805 mm / 31.7 in |
Dry Weight | 191 kg / 421 lbs |
Wet Weight | 206.0 kg / 454.2 lbs |
Fuel Capacity | 16 Liters / 4.2 US gal |