cdi test | GTAMotorcycle.com

cdi test

Pretty tough to do without the rest of the motorcycle attached - its kind of a process of elimination.
What machine are you talking about ?
 
Most service manuals that I have read just basically state "swap with known good unit" . It is possible to test one on a bench but you need a power supply, a signal generator and a really good idea of what you are doing and unfortunately I wouldn't know where to take it for that.

Check the leads and connectors at the least, look for corrosion or broken wires.
 
It's a ninja 500/ex500. The shop manual says to take it too a kawi dealer that has machine to do it. It does say that you test with a meter but the only proper way is taking to a dealer.
 
It's a ninja 500/ex500. The shop manual says to take it too a kawi dealer that has machine to do it. It does say that you test with a meter but the only proper way is taking to a dealer.

It seems the manual lies, the dealer has no "machine" to test CDIs for an EX500.

What is your problem? The EX500 CDI is pretty much bullet proof.
 
Looking to test a cdi. Just wondering if anyone has gotten this done and what they paid. Also suggestions on where to go would be great also.
Are we talking cdi, or ecu. If its ecu then it is easy to test on the bench with a multi meter and a service manual. But most shops I've been to, don't have the service manual for whatever bike the're fixing. So its replace and see if that works. Whenever I need an ecu I bring my manual and tester to zdeno or whoever is closer and test the used one I'm buying to make sure it works.
 
There is no ecu. It has carbs. There is a cdi for the ignition. Basically the bike only runs with the choke on and won't rev over 4000rpms. I have spark, compression is correct, check the timing and overhauled the carbs. I have done the cdi test with a meter as per manual. Only problems I have are that although I understand carbs I don't have a lot of experience with them and as for the cdi I have done what I can other than try another one or find a place to test one. I was hoping the test would be less expensive then replacing.
 
Is there a link between the cdi and choke, or does choke just mechanically increase the mixture? Did you check spark on both cylinders?

EDIT: I am assuming that new plugs was the first thing you tried.
 
There is no ecu. It has carbs. There is a cdi for the ignition. Basically the bike only runs with the choke on and won't rev over 4000rpms. I have spark, compression is correct, check the timing and overhauled the carbs. I have done the cdi test with a meter as per manual. Only problems I have are that although I understand carbs I don't have a lot of experience with them and as for the cdi I have done what I can other than try another one or find a place to test one. I was hoping the test would be less expensive then replacing.

The CDI a.k.a. ignition box on that bike has no knowledge of throttle position. It gets an input from the crank trigger and fires the spark plugs at the appropriate time depending on RPM only (which it knows from the crank trigger). There is no connection to engine load or throttle position or anything of the sort.

Having said that ... It takes more voltage to fire a spark plug under load (more cylinder pressure) than not, so it is entirely possible that you have spark plug cap / ignition wire / ignition coil problems. Those bikes are notorious for breaking the low-voltage wiring to the ignition coils - vibration fatigues the copper internally right at the connection to the ignition coil and only the insulation holds the wire in place even though the connection is internally broken. But usually that drops a cylinder randomly all the time.

My money is on carburetion problems, not ignition.
 
Thanks for answer Brian P. That brings me to my next question...does anyone know a good place that deals with carbs (and is good at it)?
 
... Basically the bike only runs with the choke on and won't rev over 4000rpms....


Classic EX500 clogged pilot jets... that's in the carbs.
If you check out www.ex-500.com you will find a "how to" if you want to try it yourself or look up "Ducatiman" on that site. He rebuilds CVK carbs as a service, and usually has sets on the shelf.

Here in the GTA I suggest you talk to Johnny Bent of Bent Bikes 905 273 3717
 
Classic EX500 clogged pilot jets... that's in the carbs.
If you check out www.ex-500.com you will find a "how to" if you want to try it yourself or look up "Ducatiman" on that site. He rebuilds CVK carbs as a service, and usually has sets on the shelf.

Here in the GTA I suggest you talk to Johnny Bent of Bent Bikes 905 273 3717
Pilot jets could be the issue of why it only runs off choke. By 4000 rpm the slides are back & its pulling off the mains. Could be the carbs aren't seated right in the boots, slide diaphragm could be torn or not seated properly.

I'd go through the carbs again.

Were the needles shimmed? Jets changed? Change it back to the stock settings and see if she runs.

Swap a cdi from another ex500.
 

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