Honda CBX through the years - by EMS
Date: Friday, June 06 @ 02:38:19 CDT
Although 1979 is officially the first year for Honda’s six-cylinder CBX motorcycle, first bikes appeared as early as spring of 1978, and as in some European countries the date of first registration shown in the original title determines the “origin” year of the vehicle, there are 1978 and even 1983 and 1984 CBXes being offered for sale.
Actually, the CBX was not the first six-cylinder street bike. The Italian manufacturer Benelli deserves the credit of introducing the first in-line six with the 750 Sei (Italian for “Six”), in 1976, which was largely based on Honda’s CB500 Four powerplant with two cylinders added. Benelli also invented the “jackshaft” drive for the alternator, a feature often praised as being Honda’s stroke of genius to keep the large six narrow.
1979 CBX (Z) Also often referred to as CBX- CB1, especially in Europe.
Engine Nos CB1E-2000060 to 2023296, Frame Nos CB1-2000042 to 2023175
Honda product code 422. In-line six-cylinder engine. 24-valve DOHC, two exhaust and intake valves per cylinder. 1047cc displacement. Bore X stroke 64.5 x 53.4 mm.
Compression ratio 9.3:1, rated output at crankshaft 103 hp @ 9,000 rpm.
Weight savings through use of magnesium for alternator-cover and -housing, countershaft sprocket cover, oil pick-up housing and shift linkage cover as well as hollow camshafts and an all-aluminum clutch (basket, pressure plate and cover)
Six individual 28 mm Keihin cv carburetors. 5-speed transmission, final drive 630 chain. Wheelbase 1495mm, rake 27.5º , trail 120mm.
Hydraulic brakes dual disc front 276mm, single rotor rear 295mm. Front rotors from and same as GL1000. Front calipers were from and same as CB750F, rear caliper from Goldwing. Rear rotor unique to CBX.
Silver aluminum “Comstar” wheels, front 2.15x19, rear 2.15x18, H-rated tires 3.50x19 front, 4.25x18 rear
Curb weight, full tank 272.1kg
Colors: Candy Glory Red, Perseus Silver. Black accent stripe in center with red and orange pin-stripes on tank and tailpiece. Front fender solid color. Sidecovers matte black with “CBX” logo decal. Instruments 150 mph speedometer, 11K tach and volt-meter. Indicator lights for high beam, neutral and oil pressure.
Price was $ 3,998
Note: The European models are often rated with 105hp in contemporary literature. Other differences were: Lower Handlebars, “rear-set” rider footpegs and adjustable rear shocks.
1980 CBX (A) Also often referred to as CBX-SC03. Honda product code 469.
Engine-Nos SC03E-2000025 to . Frame-Nos SC03-2000021 to..
Changes to original model: Rear swingarm with larger profile. Larger swingarm pivot diameter in the frame to accommodate increased diameter of pivot bolt from 14 to 16mm. Needle bearing on the left (chain) side and twin angular thrust bearings on the right replaced the plastic bushings from the original model. Rear shocks were now adjustable, an adaptation from the European models. Due to government regulations in Germany, limiting horsepower in motorcycles to 100hp and EPA requirements in the U.S. the engine was detuned to an output of 98hp at the crankshaft. Changes were made by rejetting the carburetors, deletion of the primary main jet, and camshaft modifications. The exhaust cam was advanced by 5º and had less overlap. The exhaust cam lift was reduced from 7.5mm to 7.0 mm, the intake cam lift was reduced from 8.3 to 7.8 mm. The mufflers, now stamped 469, had altered baffles with less back pressure. Although the engine had less power throughout the range, it no longer suffered from a very distinct “lean spot” in mid-range and deployed its power more smoothly. A modified timer advanced ignition faster and further than on the 79 CBX. The wheels were reversed Comstars, painted black. The rear rim was wider with 2.50 x18. Final drive was 530 chain. V-rated tires with same size as previous year. A 20% larger oil cooler was incorporated.
The front fork was air assist and the steering neck incorporated tapered roller bearings which were 2mm further apart. Each fork leg had two anti-stiction rings instead of one. The fork sliders were 1mm larger, 45 up from previously 44mm. Stanchions remained at 35mm. Manufacturing process of disc brake rotors was improved by using a better grinding process that would eliminate a pulsating being felt in the brake lever. Introduction of a vacuum controlled petcock to prevent the fatal “hydraulic lock” that struck some careless 79 owners.
U.S. government regulations mandated a speedometer indicating 85mph max and the last number shown on the tachometer was now 10K.
Perseus Silver was replaced by Black. A locking cable was included as an anti-theft device which was stored in a locked compartment in the tailpiece. This part was made available as an aftermarket retrofit for 1979 models, also in Perseus Silver.
A certain amount of 1980 CBXes was made in Honda’s Marysville plant in Ohio. They are believed to have all been black. Some 1980 models had painted glossy black sidecovers.
Price was $ 4,198.-
Note: The European handlebar/footpeg bracket set-up was made available in the U.S. as an aftermarket “Sport Kit” for $180.-. It included handlebars, footpeg brackets, shift lever, switches and all necessary shorter control cables and upper brake line.
1981 CBX (B) Also often referred to as CBX-SC06 Honda product code MA2.
Engine-Nos SC03E-2300060 to 2306596 Frame-Nos SC060*BC300004 to..
Major changes came in 1981 with the “B” model. In some literature in Europe, both the 1981 and 1982 CBX are designated “C” models. The CBX was turned into a “Sport Tourer”, complete with fairing and saddle-bags. The rear suspension was now a center single air shock “Pro-Link” configuration with a box profile aluminum swingarm. The front fork, still air assist but now with a single filling and balance tube, had 39mm fork tubes with syntallic bushings. Spacing between the tubes was increased by 10mm center to center to accommodate the larger diameter. Rake was increased to 29.5º. Together with the new swingarm, that increased the wheel base 40mm to 1535mm. In order to keep the trail at 120mm, the fork bridges had a larger forward offset. Brakes changed to dual piston calipers on stainless cast ventilated rotors in the front of 295mm. Rear caliper was now also twin piston, gripping a 295mm solid rotor. Wheels were forged aluminum Comstars painted black with polished edges. Rear wheel was now 2.75x18 and the front was also up with 2.50x19. Rear tire width increased to 130/90-18 (equivalent to a 5.00x18).
The engine featured significant changes also. The outside of the cases, cylinders and head was finished in black. New cams closed the intake now 5º earlier, both opening and closing of exhaust was retarded by 5º. Intake valve lift was increased by 0.2mm to 8.00mm, and exhaust valve lift changed to 7.5mm from 7.00mm. A new cam profile with a different rise and fall was supposed to reduce tappet noise. The carburetor mounting was changed to nearer horizontal for better idle, making the airbox plenum different. Together with an exhaust crossover pipe and modified header pipe lengths in the collector, these changes provided a significant increase in mid-range and roll-on power. Other changes in the engine were modified piston rings and wider valve seats (1.0mm instead of 0.7mm) to increase durability and a new, coil spring dampened clutch to reduce rattle caused by the ageing and hardening of the rubber dampeners of the early models.
All the bodywork, the shape of tank, seat, tail and side panels changed. The fairing provided room for two optional instruments. Available were a clock, an altimeter or a temperature gauge. The instrument cluster had an additional warning light for rear shock air pressure. The windshield on the European models was tinted and they still had lower handlebars and rear-set driver footpegs, although handlebars on the U.S. models was lower than on the previous models.
Only body color available was Magnum Silver with black accents and orange-red pin-stripes
1982 CBX (C) (CBX-SC06) Honda product code MA2.
Engine-Nos SC03E-2400006 to… Frame-Nos SC060*CC400001 to..
The last year production CBX was a complete carry-over from the previous year, except for the color, which was exclusively Pearl Altair White with tri-color blue accents. The rear tailpiece had a grab-handle for the passenger.
Throughout the years, improved parts replaced original designs. Many 1979 -422- parts became obsolete and were replaced with 1980 -469- parts. The plain seat, without the tailpiece, for example, was never available as a 1979 replacement. Only in a -469- configuration. While many parts interchange between 1979 and 1980 models and between 1981 and 1982 models, very few exchange between first two and last two years. And even some parts, although official Honda replacement parts for -422-, -469-, or MA2 parts may compromise fit and function and definitely originality. Good example are the MA3, Euro-CB1100, Speedometers and Tachometers which are close in appearance but ever so slightly off in their calibration.