Looking for n new part 1982 Kawasaki GT750 Speedometer Tachometer Instrument Gauge Cluster

You might have to replace the speedometer cable

Sorry but it's not a fuse problem . There is not a fuse just for the speedometer . The microprocessor inside the instrument cluster determines where the speedometer needle points , just like the fuel gauge , tachometer etc... Having the vehicle checked for DTC'S would be the proper step to take .
Vehicle Speed Signal
The vehicle speed signal is generated by the rear anti-lock brake sensor and sent to the 4-wheel anti-lock brake system (4WABS) module. The 4WABS module sends the vehicle speed signal via circuit 679 (GY/BK) to all systems which require a vehicle speed signal input.
Speedometer
The electronic speedometer receives a speed signal from the 4WABS module.

• The Speedometer/Odometer Is Inoperative

• Circuitry.
• Speedometer.

• GO to Pinpoint Test E .

No where in this factory diagnostic step does it say to check a fuse !

PINPOINT TEST E: THE SPEEDOMETER/ODOMETER IS INOPERATIVE CONDITIONS DETAILS/RESULTS/ACTIONS E1 CHECK THE VOLTAGE TO THE INSTRUMENT CLUSTER
Instrument Cluster
Measure the voltage between instrument cluster C288-7, circuit 1001 (WH/YE), and ground.

• Is the voltage greater than 10 volts?

Yes GO to E2 .

No REPAIR circuit 1001 (WH/YE). TEST the system for normal operation.
E2 CHECK THE INSTRUMENT CLUSTER PRINTED CIRCUIT
Instrument Cluster
NOTE: Measurements must be made to the speedometer gauge pins that are inside the instrument cluster printed circuit clips.

Measure the resistance between the speedometer pins (which can be seen in the middle of the instrument cluster printed circuit clips) and the corresponding instrument cluster terminal. Refer to the table for the pin and terminal assignments.

Instrument Cluster Terminal Speedometer Gauge Pin C286-13 C287-1 S C287-2 G C288-7 BATT
.

• Are the resistances less than 1 ohm?

Yes GO to E3 .

No INSTALL a new instrument cluster printed circuit. REFER to Instrument Cluster Printed Circuit . TEST the system for normal operation.
Your best bet , take it to a qualified repair shop

Should be 2240rpm = 60mph. This is pretty standard across most Japanese bikes. Pretty well any speedo will work, if it has the right fitting. I used a 1973 TS185 speedo on my GSX750 until I could get a new cluster!

The speedometer is operated differently then the tachometer. Tachometer
The tachometer displays the engine speed in revolutions per minute (RPM). Voltage pulses are taken from the ignition control module (ICM) (Gasoline) or the generator (Diesel) and sent to the tachometer. Solid state circuits convert the pulse frequency in order to move the pointer of the tachometer.

Tachometer Inoperative (Gas)
Step
Action
Value(s)
Yes
No
1
Did you perform the OBD II System Check been performed?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check (5.0L/5.7L); Powertrain On Board Diagnostic (OBD) System Check (7.4L)
2
Remove the I/P Cluster.
Disconnect the Ignition Coil connector.
Connect a J 39200 DMM (continuity) between I/P Cluster connector cavity 6 and ground.
Is continuity present?
--
Go to Step 3
Go to Step 4
3
Locate and repair the short to ground in CKT 121 (WHT) between the Ignition Coil and the I/P cluster. Refer to Wiring Repairs in Wiring Systems.
Is the repair complete?
--
Refer to Instrument Cluster System Check
--
4
Connect a J 39200 DMM (continuity) from I/P Cluster cavity 6 to ignition coil connector cavity B.
Is continuity present?
--
Go to Step 5
Go to Step 6
5
Replace the I/P Cluster. Refer to Instrument Cluster Replacement .
Is the repair complete?
--
Refer to Instrument Cluster System Check
--
6
Locate and repair the open in CKT 121 (WHT) between the Ignition Coil and the I/P Cluster. Refer to Wiring Repairs in Wiring Systems.
Is the repair complete?
--
Refer to Instrument Cluster System Check

Check online for a service manual for your bike. It would have the wiring schematic(s) you are looking for,

The "cluster" means all of the things you see under the plastic cover in front of the driver, the 'gauges'. The term is a reference to the 'instrument cluster' including speedometer, tachometer, fuel gauge, idiot lights, temperature gauge, everything.
Get a second independent opinion since this is very unusual. Most likely you have a blown fuse.

The problem here is your "Stepper Motors" are failing in the Instrument Cluster. If your Vehicle has "LOW MILEAGE" it may still be covered under factory warranty. Check with your Dealer first! If not covered under warranty, most reputable Speedometer Repair facilities can service it for you. All "Stepper Motors" in the Instrument Cluster should be replaced at the same time as the OEM versions are prone to ultimate failure.Typically, there are 5 or 6 dependent upon whether or not you have a Tachometer. They are: Speedometer, Temperature, Oil Pressure, Fuel Gauge, Volt Meter and Tachometer. The replacement part must have X25 168 where the X indicates an improved model.

Stepper motor that controls the gauge !
How to repair GM Instrument Cluster Speedometer Gauge Stepper
You can buy the step motors off amazon to do all the gauges for $27. bucks .
Amazon com Dr Roc GM Instrument Cluster Gauge Stepper Motor Repair Kit X27...

check for loose connection at the instrument cluster.