Kawasaki Motorcycle Forums banner

1 - 6 of 6 Posts

1977 KZ650
22 Posts
Discussion Starter #1

I have a 1977 KZ650 Kaw that has been running fine up until last week. Periodicaly it would die on me and I came to the conclussion that the issue was with the Ignition Switch itself (I could hear the switch shorting out internally).

After locating and installing the new switch I get nothing when I turn on the key... No horn, hazzards, attempt to start, brake lights etc.

I'm thinking the problem is either the new switch or somewhere between the switch and the battery...

Any ideas?

The electrical system's probably the only part of this bike I haven't messed with yet, but I have no problem diving in with a little bit of guidance on my solo run.



11,328 Posts
I'd suggest replacing the original fuses in the fuse clips with new ones as they have been proven to fail with time/vibration.

Fuse And Fuse Holder Designations

1. The older Kawasaki’s use a glass tubed fuse with the designation of AGX 1” long. Most good auto parts stores can get them for you. They are ¼” in diameter.

2. The more common AGC is 1 ¼” long and may not fit the smaller fuse clips. Again, ¼” in diameter.

3. To clean and polish the fuse clips, I use a cotton swab(Q- Tip) and some Brasso metal cleaner or Turtle Wax Chrome Polish. I suppose any good metal polish would work.

4. These fuses can fail internally but look good, only by removing them from the clip and electrically continuity checking with either a self powered test light, or a multimeter set on OHMS can they be determined to be in good shape.

5. A physical inspection of the metal end caps for tightness will tell you if the fuse is serviceable.

6. Most modern motorcycles are now using the automobile “Blade” style fuse with the designation of ATC or ATO.

7. The reduced sized “Mini” Blade style fuse holder uses the ATM size of fuses.

8. If the fuse and fuse holder overheat, it could soften or anneal the grip of the clip, it might require squeezing the clip to restore the tightness.

9. A list of where to purchase “Blade” style fuses and holders:

Welcome to Waytek Wire ATO/ATC STYLE COMPACT FUSE BLOCK 8 FUSE ATO/ATC Fuse Blocks Blade Fuses And Accessories Circuit Protection  - Waytek Wire

Susquehanna MotorSports - High Performance Vehicle Lighting and Competition Accessories Susquehanna MotorSports - Auto Performance Product

Del City - Wiring Products and Professional Electrical Supplies 8-way fuse block


The Dreaded Shorting/Intermittent Electrical Problem!

Here is the most basic method I know(Taken from KZrider.com - Home 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 on/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 caig.com - Home of DeoxIT - CAIG Laboratories, Inc. 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.

1977 KZ650
22 Posts
Discussion Starter #4

I got it... The fuses were alright (with a littler corrosion I decided to replace them anyways).

After that step, I proceeded to remove the tank and tear into the wireharness... After an hour of two of following the wires I Finally came across a splice that had corroded so badly that it lost it's connection...

Long story short, I'm at the library and the bike is out front. If i ride it back to Iowa this weekend I'll be sure to take some pics to post on here.

On a side note, i'd love to get another bike (a newer bike) within a year or two but I think i'll hang on to this one... Bike's older than I am and still runs nice and smooth. :)

11,328 Posts
Kawasaki for the most part on the 80's bike's used a crimped brass or copper sleeve covered in sticky black tape for joining wires. Unfortunately over time the adhesive in the tape reacted with the splice causing corrosion and intermittant electrical operation.

On my 82 GPz1100 with FI, I re-did the wiring going to the injectors as they fire on 3 volts. I had corrosion like you did, dropping cylinders with no rhyme or reason. I have experiance from eight years in the USAF working on aircraft weapons release systems and then almost 10 years at General Dynamics/Convair building missile test equipment to be able to troubleshoot and repair my bike's fuel injection system.

The repair envolved heatshrink tubing,heat shrinkable crimped splices and some special heat shrink tubing that has a meltable inner liner that when heated will shrink down about 50% and seal the joints.

If you need my sources, post back.........
1 - 6 of 6 Posts