My suzuki gs 450 1986 headlight won't turn on?

First double check the fuses. Don't just look at them. Use a continuity tester or test light. Use a test light to check for voltage from the main fuse circuit to the other circuits. If you have power in and out of the fuse box then check the relays. Lastly (or firstly if you have had the tank lifted recently and played with the airbox) check the plug connections from the main harness to the instrument panel located on the back bone just back from the steering head.

its a fuse, take it to a mecanic.

According to the 2007 owners manual for my C90T there is a 30A main fuse located behind the left upper cover. To access the main fuse lift the fuel tank lid and remove the six bolts that are holding the left and right tank covers in place (not the screws that are located under the fuel cap) then remove the two screws on the front of the speedometer/fuel inlet cover (they face the base of the handlebar risers) then remove the left tank cover and left upper cover by removing the screw at the base of the left upper cover. One 30A spare fuse should be located in the main fuse box. To access the fuse bank containing the other six fuses remove the right crank case cover, once it is cool to the touch. One 10A and one 15A spare fuse should be located in the main fuse box. Fuse list: 30A MAIN fuse protects all circuits; 10A HEAD-HI fuse protects the headlight high beam and headlight high beam indicator light; 10A HEAD-LO fuse protects the headlight low beam; 10A FUEL fuse protects the ECU, fuel pump, injectors, neutral indicator light and oil pressure indicator light; 15A IGNITION fuse protects the fuel pump relay, starter relay, ignition coils, decomp relay and solenoid; 15A SIGNAL fuse protects the turn signal indicator light, FI indicator light, speedometer lights, brake light/tail light and horn; 10A POWER SOURCE fuse protects the electrical accessories connected to the output terminal

Well the good news is the click indicates the switch is working, when you press the switch the 2poles on the solenoide are joined together alowing the current to the starter,bridge the wires at the solenoide this should put power directly to the starter you wont need to press the start switch, if the engine does not turn over check the connections to both the battery and starter motor,

instrument cluster is bad

Motorcycle DiGi Cable Colour Ground – Choose a ground wire within the harness Black Ignition switched 12 volt positive supply Red Tachometer pulse (rpm) Yellow Speedometer pulse (mph/kph) Green Neutral Light Brown Learn/set-up Orange

did you check your fuses???

Sounds like either a connector that serves the instruments, or a fuse. I would suspect a connector first off.

sounds like the alt. is on it way out