Editing Kawasaki ZX-R 750 J1

{{Infobox Motorcycle
|name             = [[Kawasaki]] ZX-R 750 J1
|image            = [[File:Kawasaki-ZXR750J-91--3.jpg|frameless|Kawasaki ZX-R 750 J1]]
|aka              = 
|manufacturer     = Kawasaki
|parent_company   =
|production       = 1991
|model_year       =
|predecessor      =
|successor        =
|class            =
|engine           = Four stroke, transverse four cylinder, DOHC, 4 valves per cylinder.
|bore_stroke      =
|compression      = 10.8:1
|top_speed        = 241 km/h / 149.7 mph
|power            =
|torque           =
|fuel_system      =
|ignition         = Digital
|spark_plug       = NGK, CR9E
|battery          =
|transmission     = 6 Speed
|frame            = Aluminium perimeter
|suspension       =Front: 43mm Upside-down forks, adjustable ride height, 13-way rebound <br>
Rear: Uni Track monoshock. adjustable ride height, preload, 4-way rebound
|brakes           =Front: 2x 320mm discs 4 [[piston]] [[calipers]] <br>Rear: Single 230mm disc 2 piston caliper
|front_tire       = {{tire|120/70ZR17 /Std Pressure 36psi}} 
|rear_tire   	  = {{tire|180/55ZR17 /Std Pressure 41psi}} 
|rake_trail       =
|wheelbase        = 1420 mm / 55.9 in
|length           =
|width            =
|height           =
|seat_height      =
|dry_weight       = 195 kg / 420.9 lbs
|wet_weight       = 221.6 kg / 487.2 lbs
|fuel_capacity    = 18 Litres / 4.7 US gal
|oil_capacity     =
|fuel_consumption =
|turning_radius   =
|related          =
|competition      =
}}

It could reach a top speed of 241 km/h / 149.7 mph.  

==Engine==
The engine was a Liquid cooled cooled Four stroke, transverse four cylinder, DOHC, 4 valves per cylinder.. The engine featured a 10.8:1 [[compression ratio]].  

==Drive==
Power was moderated via the Multi plate wet (oil submerged) [[hydraulic]] slipper clutch.  

==Chassis==
It came with a 120/70ZR17 /Std Pressure 36psi front [[tire]] and a 180/55ZR17 /Std Pressure 41psi rear tire. Stopping was achieved via 2x 320mm discs 4 piston calipers in the front and a Single 230mm disc 2 piston [[caliper]] in the rear. The front suspension was a  43mm Upside-down forks, adjustable ride height, 13-way rebound while the rear was equipped with a Uni Track monoshock. adjustable ride height, preload, 4-way rebound. The ZX-R 750 J1 was fitted with a 18 Litres / 4.7 US gal fuel tank. The bike weighed just 195 kg / 420.9 lbs. The wheelbase was 1420 mm / 55.9 in long.  
== Photos ==
[[File:Kawasaki-ZXR750J-91--3.jpg|600px|Kawasaki ZX-R 750 J1]]
[[File:Kawasaki-ZXR750J-91--4.jpg|600px|Kawasaki ZX-R 750 J1]]
[[File:Kawasaki-ZXR750J-91--2.jpg|600px|Kawasaki ZX-R 750 J1]]
[[File:Kawasaki-ZXR750J-91--6.jpg|600px|Kawasaki ZX-R 750 J1]]

== Overview ==

Kawasaki ZX-R 750-J

























The Kawasaki ZXR 750 J (J1 and J2 models) was
a 749cc sports bike released  between January 1991 and
November 1992.

The ZXR750 J was an updated version of the Kawasaki ZXR750 H1
and H2 models and featured 43mm upside down (USD) forks,
lighter, diamond section alloy chassis, new short stroke engine
and 38mm CVKD carbs (aka constant velocity carb).

Kawasaki ZXR750J

Model information
Bike model: Kawasaki ZXR 750 J
Years (in the UK): January 1991 to November 1992
Kawasaki model code: ZX750J
Frame number: Started  ZX750J-

Model and updates..
ZXR750 J1 (ZX750J1): January 1991 to December 1991. Frame number
started: ZX750J-000001-.
Available in green/blue/white or blue gitane.
Cost new (in the UK): £6379

ZXR750 J2 (ZX750J2): January 1992 to November 1992. Frame number
started: ZX750J-013901-.
Same as the ZXR750 J1 model but with minor suspension
modifications and a softer rear shock.
Available in green/blue/white or wine red
Cost new (in the UK): £6379 (price was reduced to £6249 for a
new K reg bike)



ZXR 750 J engine

Engine and gearbox
Displacement: 749cc (71 x 47.3mm)
Engine type: In-line four cylinder
Compression: 10.8:1
Power: 100 BHP
Top speed: 143.5 mph
Stroke: 4 Stroke
Oil type: 10w40 Semi synthetic
(ZXR750 J Oil filter kit  Rock Oil / ZXR 750 J Oil filter kit 
Silkolene)
Oil filter: Filtrex OIF006 / Hiflo HF303 / Champion F301
Engine oil capacity: 3.2 litres
Valves per cylinder: 4 (16 valves in total)
Cam shafts: Double overhead cams (DOHC)
Cooling system: Rock Oil Water cooled
Cooling system capacity: 2 litres
Clutch: Multi plate wet (oil submerged) hydraulic slipper
clutch
Gearbox: 6 speed
Gearbox lubrication: From engine (no separate gearbox oil)
Carburetors: 38mm CVKD Carbs
Air filter: Kawasaki part no: 11013-1210
Service kits: Silkolene / Rock Oil



Chain n Sprockets
Final drive: Chain (530 pitch chain with 110 links)
Front sprocket teeth: 14
Rear sprocket teeth: 46

ZXR750 J Radiator

Servicing intervals
Oil change: 10,000km (approx 6200 miles) or every 12 months
Cooling system change: Every 24 months (2 years)
Hydraulic brake fluid change: 20,000km (approx 12,400 miles) or
every 24 months (2 years)
Fork oil change: 30,000km (approx 18,600 miles) or every 36
months (3 years)
Swing arm pivot and uni-track grease points: Grease every
10,000km (approx 6200 miles) or every 12 months
Other grease points: Grease every 20,000km (approx 12,400 miles)
or every 24 months (2 years)

ZXR750 J race brakes

Brakes n wheels
Front brakes: Twin (dual) discs with 4 pot calipers (4 pistons
per caliper)
Front disc part numbers: EBC MD4022LS and MD4022RS
Front brake pad part numbers: EBC FA158
Rear brake: Single disc with 2 pot caliper (2 pistons)
Rear disc part number: MD4013
Rear brake pads part number: FA161
Brake systems: Front and rear hydraulic brakes
Front tyre size: 120/70-17 (3 spoke wheel)
Rear tyre size: 180/55-17 (3 spoke wheel)

ZXR750 J Carbs

Suspension stuff.
Front suspension: 43mm USD (upside down) Telescopic Forks
Front fork oil: 445ml of 5w (light weight) fork oil per fork
Rear suspension: Unitrack Monoshock

Weights n measures
Dry weight: 195kg (dry weight)
Wheelbase: 1420mm
Fuel tank capacity: 18 litres
Fuel type: Unleaded petrol

Electrics n stuff
Ignition system: Electronic CDI
Electrical system: 12 volts
Battery: YTX12-BS / CTX12-BS
Spark plugs: NGK CR9E

Other stuff.
Starter: Electric starter motor
Clutch: Hydraulic operated clutch (no cable)

1991 ZXR 750 J1

Useless stuff.
Launched in 1991 the Kawasaki ZXR750 J was based on the 1989 to
1990 ZXR 750 H1 and H2 race replica supersports bikes and there
are still plenty of these beasties around today.
The ZXR750 was a good bike in its day and was used for some
racing series and although the ZXR out handled rivals like the
GSXR750 and 1100 it was blown away a few years later (along with
the FZRs and GSXRs) by the Honda Fireblade.

The ZXR750 J was restricted to 100bhp due to an upcoming
European 100bhp ban supposedly coming to Europe around the time
the J model was launched, but, as with most European laws the
BHP ban was scrapped and never came into force.
Although the J model had less BHP then the earlier H models
(107bhp) and the later K models (121bhp), the J model had good
mid range power due to the lower brake horse power!

Although the ZXR750 J model was based on the earlier H1 and H2
models, unfortunately there arent many parts that are
interchangeable between the 2 bikes as there were numerous
changes between the H and J models (including different forks,
engine and bodywork).

Buying advice.
There are a fair few of these bikes around and you can pick up a
good example with MOT for under £1000 privately.
Because of the racing history behind these bikes there are LOADS
of ex-racers around (and racing mods like Harrison Billet 6 race
calipers can be picked up for these bikes as well!).
These bikes were built to take a knock on the track (with beefed
up yokes and spindles etc) so lightly crashed bikes can often
easily be repaired.
Obviously, the youngest of these beasts will be around 20 years
old now so the bikes do look a bit long in the tooth and will
have a few age related gremlins and they DONT handle like more
modern counterparts.
Parts to watch out for when buying..
Only parts to really check on the ZXR750 is the electrics
(alternator, CDI etc) as these can be difficult to source.
The radiators, which due to the racing design of the rad
(curved) alot of the ZXR750 radiators were used on other racing
bikes and good examples are difficult to get hold of now!
And the upside down forks.
Unfortunately, upside down forks dont fair well in the UK
weather and, unless theyve been rebuilt and the stanchions
replaced they are likely to need work and parts.

Performance mods.
Apart from the usual Dynojet and K and N filter type stuff there
is a relatively simple engine mod if you want a bit more from
your ZXR750.
If you put ZX7 pistons in a ZXR750 (it will need a rebore though
as of ZX7′s are a couple of mms bigger bore) will increase the
CC to around 790cc.
Source whitedogbikes.com


The Kawasaki ZXR750 was perhaps the most
brutal, most mental of all the Japanese 750s ever. While the
bike was launched way back in 1989, its blue/green/white colour
scheme and hoover-tube air-intakes are instantly recognizable
icons in the world of high-performance motorcycling even now.
There was about 100 horsepower on tap. Top speed was around
250km/h. And the chassis/suspension combo was tuned with
single-minded focus  to get you around corners as fast as
possible.

The ZXR750 was replaced by the ZX-7R (and the more race-oriented
ZX-7RR) in 1993, and these bikes remained in production till
2003. The ZX-7RR was raced successfully by riders like Scott
Russell and Doug Chandler, whose combined efforts resulted in
four AMA championships for Kawasaki, over a period of seven
years. Russell also took the 7RR to World Superbikes, where he
won the 1993 WSB championship.

The ZXR750 and the ZX-7R were significant superbikes of their
time and kept Honda VFRs, Suzuki GSX-Rs and Yamaha YZFs on their
toes!
Source
{|  class="wikitable"
|- 
!Make Model
|Kawasaki ZX-R 750-J
|- 
!Year
|1991
|- 
!Engine Type
|Four stroke, transverse four cylinder, DOHC, 4 valves per cylinder.
|- 
!Displacement
|749 cc / 45.7 cu-in
|- 
!Bore X Stroke
|71 x 47.3 mm
|- 
!Cooling System
|Liquid cooled
|- 
!Compression
|10.8:1
|- 
!Lubrication
|Wet sump
|- 
!Engine Oil
|10W/40
|- 
!Induction
|4x 38 mm Keihin CVKD (Constant Velocity) carburettors / Ram Air System (single intake)
|- 
!Ignition
|Digital
|- 
!Spark Plug
|NGK, CR9E
|- 
!Starting
|Electric
|- 
!Max Power
|100 hp / 74 kW @ 10500 rpm
|- 
!Max Power Rear Tire
|92.8 hp / 69.2 kW @ 10700 rpm
|- 
!Max Torque
|7.45 kgf-m / 53.8 lb-ft @ 9000rpm
|- 
!Clutch
|Multi plate wet (oil submerged) hydraulic slipper clutch
|- 
!Transmission
|6 Speed
|- 
!Final Drive
|Chain
|- 
!Frame
|Aluminium perimeter
|- 
!Front Suspension
|43mm Upside-down forks, adjustable ride height, 13-way rebound
|- 
!Front Wheel Travel
|120 mm / 4.7 in
|- 
!Rear Suspension
|Uni Track monoshock. adjustable ride height, preload, 4-way rebound
|- 
!Rear Wheel Travel
|120 mm / 4.7 in
|- 
!Front Brakes
|2x 320mm discs 4 piston calipers
|- 
!Rear Brakes
|Single 230mm disc 2 piston caliper
|- 
!Front Tire
|120/70ZR17 /Std Pressure 36psi
|- 
!Rear Tire
|180/55ZR17 /Std Pressure 41psi
|- 
!Rake
|24.5°
|- 
!Trail
|95mm / 3.74 in
|- 
!Wheelbase
|1420 mm / 55.9 in
|- 
!Dry Weight
|195 kg / 420.9 lbs
|- 
!Wet Weight
|221.6 kg / 487.2 lbs
|- 
!Fuel Capacity
|18 Litres / 4.7 US gal
|- 
!Consumption Average
|16.3 km/l
|- 
!Braking 60 - 0 / 100 - 0
|13.3m / 37.1m
|- 
!Standing ¼ Mile
|11,2 sec / 196.2 km/h
|- 
!Top Speed
|241 km/h / 149.7 mph

|}
== External Links ==
* http://www.fasterandfaster.net/2014/06/ss-xr1200rr-sportster-is-simply-magical.html

[[Category:Kawasaki motorcycles]]