The CX650 was released in 1983, and came in three flavours – the CX650C, C650ED and CX650 Turbo.
Features
The CX650 variants were significant upgrades from most of their 500 brethren. The CX650ED Eurosport shares much with the previous year’s CX500EC; notable improvements as compared to other CX500 variants include the tubular frame, dual twin-piston caliper brakes, monoshock rear and a new tank with fuel gauge. The CX650C was a cruiser-oriented bike aimed at the US market, and had it’s own frame with a lower seat, teardrop tank and shorter exhaust giving it quite a different look to the other CX650s in 1983’s lineup.
The CX650 Turbo was an improvement on the CX500 turbo; changes were made to the compression ratio and boost pressure to make for a less abrupt transition to being on-boost. The fuel injection system was also updated, and the rear monoshock gained a manual damping control mechanism.
CX650 and CX650 Turbo History
The entire CX650 lineup was for a single year only – 1983. Apparently only 1,777 examples of the CX650 Turbo were ever made. We don’t have solid numbers on the CX650C and CX650ED.
The 650 variants were the final iterations of the twisted twin – and Honda has not revisited the design since.
Regional Variants
Australia
The CX650C was not sold in Australia, but the CX650ED was. You can find CX650Cs for sale from time to time as imported bikes. There were two Honda motorcycle importers to Australia in ’83, each servicing different states (Bennett did NSW and QLD, MPE did VIC, TAS, SA and WA) – one brought in red and white bikes, the other black and white bikes.
Canada
The CX650ED was sold here.
Europe
The CX650E was sold in Europe. Germany had a restricted version available, which had 37kW of power – essentially restricting it to the kW of the CX500.
North America
The CX650C was sold here, but the CX650E was not. The CX650T was sold here!
CX650 Performance
CX650ED
CX650C
CX650 Turbo
Power
45kW (60hp) @ ?
45kW (60hp) @ ?
75kW (100hp) @ 8,000rpm
CX650 Dimensions
CX650ED
CX650C
CX650 Turbo
Length
2,250mm (88.6″)
2,180mm (85.8″)
2,220mm (87.4″)
Width
760mm (29.9″)
790mm (31.1″)
775mm (30.5″)
Height
1,190mm (46.9″)
1,165mm (45.9″)
1,325mm (52.2″)
Wheelbase
1,500mm (59.1″)
1,515mm (59.7″)
1,495mm (58.9″)
Seat Height
795mm (31.3″)
780mm (30.7″)
790mm (31.1″)
Foot Peg Height
320mm (12.6″)
?
Ground Clearance
150mm (5.9″)
155mm (6.1″)
145mm (5.7″)
Dry Weight
210kg (463lb)
196kg (432lb)
235kg (518lb)
Wet Weight
230kg (507lb)
210kg (463lb)
256kg (564lb)
CX650 Frame, Wheels and Tyre Specifications
CX650E Eurosport
CX650C Custom
CX650 Turbo
Type
Diamond Type
Rake
28 degrees
32 degrees
27 degrees
Trail
105mm (4.1″)
126mm (5.0″)
109mm (4.3″)
Front axle type
In-line
Leading
In-line
Front suspension
Telescopic fork with anti-dive
Telescopic fork
Telescopic fork with anti-dive
Front fork diameter
37mm
39mm
37mm
Front fork oil capacity
290cc left, 275cc right
480cc per leg, after disassembly
310cc per leg, after disassembly
Front suspension travel
150mm (5.9″)
160mm (6.3″)
130mm (5.1″)
Front suspension air pressure
0-6psi
Rear suspension
Pro-Link Monoshock, Swingarm
Dual shocks, swingarm
Pro-Link Monoshock, Swingarm
Rear suspension travel
110mm (4.3″)
120mm (4.7″)
105mm (4.13″)
Rear suspension oil capacity
270cc
?
?
Rear suspension air capacity
180cc
N/A
260cc
Rear suspension air pressure
0-71psi
N/A
28-85psi
Front wheel type
Boomerang Comstar
Cast alloy
Boomerang Comstar, silver
Front tyre size
100/90, 18 56 H
100/90, 19 57 H
100/90, V18
Front tyre pressure
32psi, any load
36psi, any load
Rear wheel
Boomerang Comstar, ?”
Cast alloy
Boomerang Comstar, silver
Rear tyre
120/80, 18 62 H
140/90, 15 70 H
120/90, V17
Rear tyre pressure
32psi <90kg load, 40psi >90kg
36psi <90kg load, 41psi >90kg
CX650 Brake Specifications
CX650E Eurosport
CX650C Custom
CX650 Turbo
Front Brake Type
Dual disc, twin piston
Single disc, twin piston
Dual disc, ?
Front Brake Diameter
276mm (10.9″)
?
?
Swept Area
952cm²
516cm²
952cm²
Rear Brake Type
Single disc
Drum
Single disc
Rear Brake Diameter
276mm (10.9″)
?
?
Swept Area
476cm²
201cm²
476cm²
CX650 Engine Specifications
CX650ED
CX650C
CX650 Turbo
Type
4 stroke, OHV, liquid cooled
Engine Weight
74.5kg (164lb)
78kg (172lb)
Bore
82.5mm (3.25″)
Stroke
63mm (2.48″)
Displacement
674cc (41.1cu)
Compression ratio
9.8:1
7.8:1
Cylinder compression
171psi
100-142psi
Lubrication system
Forced pressure, wet sump
Oil Capacity
After draining
3.0L (3.2 US qt)
After disassembly
3.6L (3.8 US qt)
Cooling system
Electric fan, radiator
Cooling system capacity
After draining
1.7L (1.8 US qt)
1.5L (1.6 US qt)
After disassembly
2.08L (2.2 US qt)
2.1L (2.2 US qt)
Radiator Cap Release Pressure
10.7-14.8psi
?
CX650 Valvetrain Specifications
CX650ED
CX650C
CX650 Turbo
Valvetrain
Chain driven camshaft + pushrod
At 0mm lift:
Intake valve opens
87°50′ BTDC
84° BTDC
Intake valve closes
121°04′ ABDC
108° ABDC
Exhaust valve opens
107°26 BBDC
80° BBDC
Exhaust valve closes
82°26 ATDC
104° ATDC
At 1mm lift:
Intake valve opens
7° BTDC
5° BTDC
Intake valve closes
53° ABDC
30° ABDC
Exhaust valve opens
40° BBDC
30° BBDC
Exhaust valve closes
15° ATDC
5° ATDC
Intake valve clearance, cold
0.10mm (0.004″)
Exhaust valve clearance, cold
0.12mm (0.005″)
CX650 Fuel System Specifications
CX650ED
CX650C
CX650 Turbo
Fuel Tank Size
12.4L (3.28 US gal)
20L (5.3 US gal)
Fuel Tank Reserve Level
2.2L (0.58 US gal)
5L (1.3 US gal)
Type
Twin carburetors
Fuel Injection
Carburetor type
Constant vacuum piston valve
N/A
Carburetor IDs
VB2BA, VB2BB (G1), VB2BC (G2)
VB2AC
N/A
Pilot screw initial opening
2-3/8
N/A
Float level
15.5mm (0.61″)
N/A
Fuel pressure
N/A
36.3psi
Minimum RON
94 RON
CX650 Drive Train Specifications
CX650ED
CX650C
CX650 Turbo
Clutch
Wet, multi-plate
Transmission
5-speed, constant mesh
Drive Method
Shaft
Primary reduction ratio
2.114 (74/13)
1.725 (69/40)
1st gear ratio
2.5 (40/16)
2nd gear ratio
1.714 (36/21)
3rd gear ratio
1.280 (32/25)
4th gear ratio
1.035 (29/28)
5th gear ratio
0.838 (26/31)
Final drive ratio
3.090 (34/11)
3.400 (34/10)
Final drive oil capacity
170cc (5.7 US oz)
160-180cc (5.4-6.1 US oz)
CX650 Electrical Specifications
CX650ED
CX650C
CX650 Turbo
Ignition type
Transistorised
Ignition timing “F” mark
15° BTDC @ 1,100rpm
10° BTDC @ 1,100rpm
Full advance
40 +/- 1.5° BTDC @ 3,500rpm
Starter
Electric only
Alternator
AC generator, 12V, 252W @ 5000rpm
AC generator, 12V, 252W @ 5000rpm
AC generator, 12V, 350W @ 5000rpm
Battery capacity
12V – 14ah
Spark Plugs – standard
NGK DPR8EA-9
NGK DPR8EV-9 NGK DPR7EV-9 below 0°C
Spark Plugs – extended high speed riding
NGK DPR9EA-9
NGK DPR9EV-9
Spark Plugs – Iridium
Spark Plug Gap
0.8-0.9mm (0.031-0.035″)
Fuses
30A main fuse, 15A sub-fuses
30A main fuse, 15A and 10A sub-fuses
30A main fuse, 15A sub-fuses, 10A fan motor fuse
CX650 Light Bulb Specifications
CX650ED
CX650C
CX650 Turbo
Voltage
All 12V. CP = candlepower # – SAE no.
Headlight – high/low
60/55W
60/55W (Phillips 12342/99 or equiv.)
Tail/brake light
21/5W, 23/8W (U)
8/27W, 3/32cp, #1157
Turn signal or indicator, front
21W, 23W (U)
32cp, #1034
23W, 32cp, #1073
Turn signal or indicator, rear
21W, 23W (U)
23W, 32cp, #1073
2 thoughts on “CX650 Specifications, Features, History and Regional Variants”
james francis knight
gday,
really great to have expert knowledge on my 40 year old machine CX650 1983 RC11 version or the ‘Yank’ as its so rare and yet a real and absolute beautiful machine,
nbest regards and a big thankyou
regards
J F Knight
(LIthuania)
gday,
really great to have expert knowledge on my 40 year old machine CX650 1983 RC11 version or the ‘Yank’ as its so rare and yet a real and absolute beautiful machine,
nbest regards and a big thankyou
regards
J F Knight
(LIthuania)
Glad you have found the site helpful – most welcome!