ive noticed there have been a few threads asking similar questions about the ignition system. most have been answered, but i figured, id condense those responses here, and we can make this the penultimate thread on ignition system troublshooting.
its been said that a 4 stroke engine needs 3 things to run: air, fuel and a spark at the right moment. i would say FOG is the resident expert on the first two. i am NOT
claiming to be an expert on the ignition system of our bikes by ANY stretch of the imagination. in fact, much of what ive written here comes directly from the haynes or chilton manuals. that said, i have done pretty much everything described herein. its not very hard at all. i think that the ignition system is less complicated than the fuel/air delivery systems, and can easily be serviced by novices and beginners alike with little to no experience turning wrenches on their bike.
so... on we go.
tools you will need
a multimeter. buy one, or borrow one from a friend. you can get them at autozone, wal mart, ebay... pretty much anywhere that sells tools should have these. they are not very expensive. for what you will be doing on the bike, one that costs 20 bucks should do the trick. if you have an advanced degree in electrical engineering, you can buy ones that cost upwards of 1500 US dollars. the 20-30 dollar range ones will work great here.
an 18mm deep well thin wall socket to get the spark plug out. i got mine at craftsman (i think its part number 44423... at least thats the number stamped on it.). i didnt have to modify it to get it to fit, it fit like a glove the first time
i think it was like 4 bucks?
a spark gap tester. for this, you can just use a spark plug, but i think its better to build this one. reason being, the spark plug gap is .6 to .7mm. a healthy system should be capable of jumping 6 -8 mm (1000% more distance) depending on your model. makes it much easier to see. also, you can have a weak spark that will jump half a mil, but not 6 mm. you can see the color of the spark better too. it costs 30 cents and takes 15 minutes. you may be able to build it with parts you already have in your garage.
Spark Gap Tester Instructions
take piece of wood about 3"x3"x1" or so. size isnt really important, but you dont need it to be huge. drill a hole about 1" in diameter in the middle. screw an alligator clip onto one corner. take two nails and put them in across from each other, such that the tips of both screws meet in the center of the hole you drilled. make the gap between the two tips as specified below for your model. you can use small carpeting nails or something like that. cut off the head of one of the nails so that it is flush with the wood, and make sure the other one sticks out a bit. it needs to stick out far enough that it will get all the way up into the spark plug cap.
gap should be 6mm for EX500D models, 7mm for EX500A models and 8mm for ER models.
now to the troubleshooting:
step one is make sure that you are getting a spark to your plugs.take the spark gap tester i described above, and clip the alligator clip onto a good ground. i find a valve cover bolt works well. take the spark plug cap off of the plug on whichever cylinder you are working on, and stick it onto the longer nail.
if you are just using a regular spark plug for whatever reason, just take the cap off, and use another plug.
whatever you use LEAVE THE PLUG IN THE CYLINDER HEAD
. if you take the plug out of the head and just let it dangle there, when you crank the engine, gasoline will spray out of the plug hole, and combined with the sparking from the plug, you could cause a major fire. if you leave the one in there, you alleviate this potential hazard. make sure the tip of the plug is not touching any metal as well, because you wont get any spark that way, it just goes straight to ground.
another caveat: do not shock yourself please. when doing these tests dont touch the spark plug wire. dont touch the spark plug. dont touch the gap tester. its best if you do not even touch the bike, except for the start button. if you touch the wire, plug, gap tester, etc you could, at worst, BE KILLED (as in no more! ceased to be. expired and gone to meet your maker. a stiff. bereft of life. rest in peace. if you hadnt been nailed to the seat, youd be pushing up the dasies. your metabolic processes are now history. off the twig. kicked the bucket. shuffled off your mortal coil. run down the curtan and joined the bloody choir invisible. AN EX PERSON ) and, at very least, be knocked on your a$$ and your arm tingle for an hour (ask me how i know). just use common sense and dont electrocute yourself.
now whichever option you've chosen, you got your plug wire connected to either the gap tester, or another plug and are ready to check the spark. push the start button. the bike may start and run on the other cylinder. you should see a fat blue spark jump between the gap of the tester you built. now turn your bike off.
if you see the spark, then your ignition system is working correctly. consider renewing your plugs, and look into fuel and air delivery, because your problem, most likely, does not reside in the ignition system.
if your spark is weak (orange) skip down to the ignition coil section. if you get NO SPARK AT ALL then you need to check for poor contact at the plug cap and ignition connectors. repair any that are damaged and recheck for spark.
if contact is fine then unscrew the plug cap from the plug wire and check the resistance with your multimeter. set the meter to k-ohms (k Ω). stick one prong in where the wire went in and stick the other prong in where the plug goes. if the multimeter reads infinity, get a new spark plug cap.
the cap resistance should be 3.75 to 6.25 K-ohms on EX500D (94+) models. my manual says that the information for the pre 94 models is
next thing to check is make sure all the other connections are clean and tight. (coil to lead, coil terminals, etc) check wires for fraying, burning, shorts etc.
if everything checks out and you still have no spark, check the operation of the following switches: a) neutral b) ignition c)engine kill
if they are broken, replace and retest. if they are fine, continue on to the...
you need to check the primary and secondary resistance of your ignition coils. with the bike off (key and switch), here is how to do it:
M is your multimeter
1 is the primary resistance
2 is the secondary resistance
you want your multimeter in the ohm setting for the primary.
if the primary is as specified, then check the secondary. put the multimeter in K-ohms for the secondary.
if the secondary is not as specified, unscrew the spark plug lead and retainer from the coil, detach the lead and check it again. if it is now within specs, the lead is broken internally. if not within spec, the coil is probalby defective and should be renewed.
primary: 2.2 to 3.9 ohms
secondary: 10 to 16 K-ohms
EX500D and ER:
primary 2.3 to 3.5 ohms
secondary 12 to 18 K-ohms.
if everything here checks out you move on to:
the pickup coil wiring harness is located here:
you need to take off the front sprocket cover to access it.
follow the pick up coil wiring harness from the point where it leaves the alternator cover to the electrical connector, then disconnect the connector for the pick up coils. 500A models have two pickup coils and the connector will have four wires, whereas 500D and ER models have a single pick up coil with two wires leading to the connector.
set your multimeter to ohms. measure the resistance on the engine side of the wire connector. on A models, connect the meter probes between the black and yellow wire terminals of the connctor for one coil, then between blue and black/white wire terminals for the other coil. on D and ER models, you only have black and yellow.
500A: 400-490 ohms
500D and ER models: 360-540 ohms
now set the ohmmeter on the highest resistance range. measure the resistance between a good ground and each terminal in the connector. the meter should read infinity.
if either test fails the coils need replaced. although check that the fault is not caused by corrosion in the connector, or a broken wire
if both tests pass, and all connections are clean and tight, all wires are in good condition, then you can be fairly safe in saying that all components are good. at this point you can consider the IC igniter
defective by process of elimination
the IC igniter is not servicable, and must be replaced as a unit. i recommend you take it to a kawa dealer to be checked. it is a very expensive unit which could be damaged by inadvertently applying the wrong test connections. oftenthe best way to test it is to swap another one out from a running bike.
it is rare for the IC igniter to fail and it should last the life of the motorcycle. check all other ignition components before having the igniter tested.
thats it! feel free to add any information, or ask any questions if you something isnt clear. remember, ASKING QUESTIONS IS NOT AN ADMITTANCE OF IGNORANCE. IT IS AN ATTACK ON IGNORANCE.