Yamaha XJ750-D Fuel Injection (Model 22N)1984.

Yamaha XJ750-D Fuel Injection (Model 22N)1984.

This bike is a little more unusual. It was made for the Japanese home market only and is one of the earliest examples of fuel injection used on a motor cycle.

It is based on the same body style as used on the Yamaha XJ-650-Turbo.

It boasts a fully digital dash board with a ten function on-board fuel economy computer that includes a clock, up-count trip meter, set-able down-count trip meter, fuel remaining in tank (ltrs), fuel economy (as you ride, updated every 30 seconds) range on remaining fuel, time spent on trip, average speed, fuel consumption, and average economy.

There is also a seven function monitor that activates a large warning light on the dash and displays an LCD icon to warn if the side stand is down or brake, oil, battery or fuel levels are low. It also warns of lamp failure in the head or tail lights and provides a fuel gauge.

Originally these bikes were all silver with either red or gray decals depending on year of manufacture.

When I purchased my injection the previous owner had repainted it blue with red pearl, I liked the change so kept it. I am not really keen on the original silver paint work.

The fuel injection is the electronic multi point type with the injectors housed in four simple throttle body's with the usual cable actuation via a twist grip on the right handle bar.

Intake air flow is monitored by an airflow sensor in the air box and a boost sensor piped to one inlet manifold.

The fuel pump is an electric 'disk and roller' type pump. Normally these bikes use a Hitachi pump but mine had failed and the closest equivalent I could find was a Airtex EP6910 EFI pump. It seems to perform well.

The engine / gearbox and final drive are the same as used on the other early 1980's XJ 750's.

Specifications;

Model		YAMAHA XJ750-D
Frame No.		5G8-021058
Engine Model		5G8
Manufactured since		Aug.1982
Dimensions	Overall Length	2170 mm
	Overall width	730 mm
	Overall height	1365 mm
	Seat height	785 mm
	Wheelbase	1440 mm
	Minimum road clearance	140 mm
Weight	Dry	231 kg
Weight	With oil and full fuel tank	254 kg
Seating capacity		2
Performance	Climbing capacity	30¡
	Minimum turning radius	2700 mm
	Stop length	15 m (50km/h)
Engine	Type	4 stroke, gasoline, air-cooled, DOHC
	Cylinder	4-cylinder, inline type
	Displacement	748cm^3 (45.6 cu.in)
	Bore x stroke	65.0 mm x 56.4 mm
	Compression ratio	9.2
	Compression pressure	9.0kg/cm^2 - 300rpm
	Horsepower	70PS/9000r.p.m.
	Torque	6.2kg-m/7000r.p.m.
	Air cleaner	Dry type
	Clutch type	Wet, multiple-disk
	Gear box type	Constant mesh, 5-speed forward
	Starting System	Electric starter
	Ignition System	Battery ignition (Full transistor ignition)
Chassis	Frame type	Double cradle
	Steering: Caster	28¡
	Trail	115 mm
	Angle	Each 35¡
	Fuel tank capacity	19 L
	Braking system: Front	Double disk brake/Right hand operation
	Rear	Drum brake/Left foot operation
	Suspension: Front	Telescopic fork with anti-dive
	Rear	Swing arm
	Shock absorber: Front	Coil/air spring, oil damper
	Rear	Air/gas/coil spring, oil damper
	Tire size: Front	3.25H19-4PR (100/90R19 57H) Tubeless tire
	Rear	120/90-18 65 Tubeless tire
Gear	Primary reduction ratio	97/58 (1.672)
	Ratio	First 35/16 2.187 Second 30/20 1.500 Third 30/26 1.153 Fourth 28/30 0.933 Fifth 26/32 0.812
	Secondary reduction ratio	48/37 x 19/18 x 32/11 (1.297 x 1.055 x 2.909)
Engine oil quantity	Periodic oil change	2200 cm^3
	With oil filter replacement	2500 cm^3
	Total amount	3200 cm^3
Fuel injection system	Type	Injector
	Nozzle	Ball type, 1 for each cylinder
	Injector diameter	0.55 mm
	Idling	1050 r.p.m.
	Idling boost pressure	>185 mmHg
Tire air pressure	1 passenger	Front 1.75kg/cm^2 Rear 2.00kg/cm^2
	2 passengers	Front 2.00kg/cm^2 Rear 2.25kg/cm^2
	High speed	Front 2.00kg/cm^2 Rear 2.25kg/cm^2
Battery	Type	SYB-14L-A2
	Capacity	12V, 14Ah
	Regular charge	1.4 A x 10 hour
Generator	Type	LD119-19
	Manufacturer	Hitachi, Ltd.
	Voltage	12 V
	Output	14V-26A
Regulator	Type	S8534
	Manufacturer	Nippon Denso, Ltd.
	Regulation voltage	14.5 V
Starter	Type	ADB4D2
	Manufacturer	Nippon Denso, Ltd.
	Voltage	12 V
	Output	0.6 KW
Ignition coil	Type	CM12-09
Ignition coil	Manufacturer	Hitachi, Ltd.
Spark plug		NGK BPR7ES,BP7ES Nippon Denso W22PR,W22EP
Electrical	Headlight	12V,60/55W (Halogen Bulb, Quartz)
	Tail/brake light	12V,27/8W x 2
	Marker light	12V,3.4W
	License light	12V,3.4W x 2
	Flasher light	12V,27W x 4
	Meter light (Tachometer)	12V,3.4W
	Meter light (Speedometer)	12V,2W x 5
	Pilot lights:NEUTRAL	12V,3.4W
	HIGH BEAM	12V,3.4W
	SPEED ALARM	12V,3.4W
	TURN	12V,3.4W x 2
	ALARM INDICATOR	12V,3.4W