ELectrical short keeps blowing fuses

I just got this bike about a month ag0,

a 1980 kz 750

and now its dead.

the battery died and jumped it to get home, I charged the battery over night then took it out again, and this time it cut out, while i was on it, lights power everthing, when i go to turn the key the nuetral light wouldn't come on.
SO i check the battery, is fully charged, I check the connections which are also good. I checked the fuses, my main fuse was blown, I replace it, turn the key and the nuetral light comes on for literally a second, only to die again. I check again and the new fuse is blown. I think I have a short somewhere, but dont know what to do at this point to fix or even find the source of the problem.

Anyone have any experience like this or an advice for fixing the problem?

I'm not familiar with that bike, but some things you could do is start by unpluging devices from the wire harness. When you get to one and the fuse doesn't blow then follow that harness. You could temporarily connect a circuit breaker of the same amperage as your main fuse so you don't have to keep buying new fuses.

Another trick to see if there's actually a short is to connect a test light between the negative battery cable and negative terminal on the battery. If the test light lights up there's a short.

Sound like you definetly have a short. You just have to start tracing wires. One at a time,pay attention to any spot where the wire comes in contact with the frame.

The Dreaded Shorting/Intermittent Electrical Problem!


Here is the most basic method I know(Taken from www.kzrider.com by member Patton)

1. Charge your battery and have it load tested if you can. The floating ball hydrometer can be used to check the specific gravity of the charged cells in the battery.

2. Disconnect the Black lead from the (-) Battery terminal... or Red from the (+) Battery terminal, it does not matter which one.

3. Connect one of the following test setups in series with the Battery terminal and lead:
3.1 A 12 V light bulb,
3.2 A 12 V test light,
3.3 A 12 V test buzzer or,
3.4 A 12 V horn... you get the idea.

4. With the Ignition Switch OFF, go through your harness and wiggle the wires while looking/listening for the test setup to go on/start buzzing.

5.With the Ignition Switch ON, repeat the test except this time the looking/listening for the test setup to go off/stop buzzing.

6. Be prepared to open the Ignition switch and check/test for solder joint failure and or circuit board micro breaks (don't ask how I know this ).

7. Be prepared to pull the wires out of the Head Light to test for failures at or near the grommet.

8. Be prepared to open the harness at or near the Steering Neck for failures. This is where wires tend to exhibit fatigue due to repetitive movement.

9. Be prepared to open the left and right switch gear to search for rust and or broken parts. CAUTION: watch out for flying springs, ball bearings and stuff. Do indoors on White sheet (again don't ask ).

10. Be prepared to follow the heavy gauge wire from the Starter Solenoid (Relay) to the starter for bare wire exposure. Especially near bends and grommets.

11. If you can reproduce the fault symptom your are pretty much home free. Be prepare to find and repair/replace any internal wire breaks, insulation break downs, exposed wires, rubber grommet failures, etc. Often, shrink tubing will solve the problem temporarily until something better can be done.

12. I use a very good electrical contact cleaner/preservative called De-oxit made by Caig Labs in San Diego Ca. Their website is www.deoxit.com It can be purchased at Radio Shack and any other electronic supply store. I use it on all of my motorcycle’s electrical connectors , in my home entertainment center’s stereo patch cords and cordless phones charging cradles.