only running on 2 cylinders

i have a 78 kz650c2. its only running on cylinders 1 & 4. 2 & 3 are getting fuel and points gap is correct. I'm thinking it could be the ignition coil or maybe the timing is alittle off.( not sure how to test either). Any suggestions?

I'm having similar issues. Here is the testing procedure as provided by MFolks:


Testing Kawasaki Ignition Coils For Input Voltage

When voltage testing Kawasaki Ignition Coils, the following needs to be done:

1. Remove the fuel/gas tank to access the coils.

2. Fully charge the battery.

3. Using a multimeter, set it up for VDC(Volts, Direct Current), range of 20.

4. Turn on the ignition switch and the run/stop switch to “Run”.

5. Put the multimeter’s RED probe on where the red or red/yellow wire goes on the ignition coil.

6. Put the multimeter’s BLACK probe on either the battery Negative(-) post/terminal or a good frame ground.

7. You should be able to see battery voltage at the ignition coil connection, but this depends on the current draw of other items in the same circuit.

8. If the tested voltage is down to 8-9 volts, you probably need to clean the many and various electrical connectors.

9. To check the spark output at the sparkplugs, use these:
Ignition Spark Testers
www.lislecorp.com/divisions/products/?pr...ion=1&category=8
www.lislecorp.com/divisions/products/?pr...ion=1&category=8 Instead of grounding the sparkplug with the sparkplug wire attached, looking for a spark. This method puts the IC Igniter and ignition coils at risk of failure due to high currents, and possible internal shorting.


Ignition Coil Primary And Secondary Wiring

Ignition coils on the 80’s Kz1000,Kz1100’s and Gpz1100’s are wired the same, that is as you sit on the bike, the LEFT ignition coil primary(small wires) are two wires, RED and BLACK. The secondary (or sparkplug wires) go to #1 and #4 sparkplugs(your primary wiring may be different).

The 550’s, 650’s, 700’s & 750’s are backwards to what is listed for the bigger 4’s.

The cylinders are numbered left to right as you sit on the seat; #1,#2,#3, and #4.

For the RIGHT ignition coil, the primary wires, again are two wires, RED and GREEN, with the secondary going to #2 and #3.

The RED wire gets it’s voltage from the run/stop switch on the right handlebar switch pod. Your primary wiring may have a different color.

The BLACK and GREEN wires connect to the IC Igniter(if the bike has the Kawasaki supplied electronic ignition) it actually gives the coils their grounds to fire the sparkplugs.

Primary(small wires) side of the coils will read between 1.8 to 3.0 ohms.

Secondary(sparkplug wire ports)side of the coil will read between 10.4K to 15.6K ohms. These ports are wired together, so it makes no difference which is used, as long as the correct coil to sparkplug configuration is followed.

The sparkplug caps should read 5K OHMS(5000), any higher, or a reading of infinity means new caps should be ordered. When re-installing the old or new sparkplug caps, cut about ¼” off the sparkplug wires for a new un-corroded connection.

Never run supression sparkplug wires with sparkplug caps containing the 5000 ohm resistor, as now there will be two (2) resistances in the ignition coil’s secondary circuit, causing weak and intermittent spark.


To stress the ignition coils, take a hair dryer, heat the coils and see if the ohm readings change from cold to hot . If they do, it’s time to buy new coils.

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Keep in mind, the wiring is reversed for the 550’s, 650‘s,700’s, and 750‘s, that is the RIGHT coil primary will be two wires, RED and BLACK with the secondary(sparkplugs) going to #1 and #4.

The LEFT coils primary wiring would be again two wires, RED and GREEN, with the secondary(sparkplugs) going to #2 and #3.

An indication of black and sooty sparkplugs may not mean a carb or carbs are in need of cleaning, but may mean the input voltage is low.

When checking the input voltage to the ignition coils, first have a fully charged battery, and the using a multimeter, set it up to measure VDC(Volts, Direct Current), range of 20.

Put the RED probe from the multimeter on the same terminal that either a RED wire or ones that’s RED with YELLOW stripe, and the BLACK probe on either a good frame/Earth ground or the battery Negative(-) terminal/post.


These engines have what is known as a “Wasted Spark” that is, a sparkplug will fire during an exhaust stroke. It does no damage and many other motorcycle engines have this design.

One quick and easy way to test if it is a bad coil is to temporarily swap the coils. If you move the 1&4 coil to cylinders 2&3 and the 2&3 coil to cylinders 1&4 does the bike still run on 1&4? If it does, both coils are ok. If the swap causes the bike to run on 2&3 you have identified a bad coil. Ed