No spark tried a lot of things looking for some help

[Zanrith]

Hello everyone as the title suggest looking for some help. Friend bought a 2005 Ninja 250 (EX250 F19) that we were told has spark. Well, we don't.

What I've done so far:
Tested the ignition coils
Tested the 100 ohm grey wire resistor
Tested the pickup coil
Tested the stator
Tested the CDI (But the part number says it is for a 2006-2007 so this might be the problem)
Replaced the junction box because the relay wasn't clicking on the starter circuit. New one works and clicks strong.

Jumped the side stand switch and handle bar safety switch.
Jumped Brown to Grey and White on the key switch to eliminate all other circuits from the issue.

Ignition coil on both positive and negative sides read 12v with the key on.
I am getting some sort of signal to the ignition coil when pressing the start button.

The CDIs we have are part number 21119-0010 and 21119-0012 which if I go on Partzilla show up as used on the 2006 & 2007 one is a US model one is a CA model.

I don't believe we have a CA model because there is no extra fuel evap system that is shown on Partzilla.

Not sure if the wrong CDI is our issue or if we have something else going on. I have downloaded a repair manual and a supplemental repair manual and have a haynes repair manual. And I've been to faq.ninja250.org and downloaded all of the color coded diagrams on there and tested everything I can think of. Besides the wrong CDI I am not sure what else could be wrong so I am looking for help. Thanks already for all the great information I've found on this site I've read so damn much.

[Zanrith]

Hopped in the garage last night to do some more testing.
Turn the key on and neutral and oil light turn on like normal.
12v coming out of the Grey wire to CDI
12v to the ignition coils.
Hit start button and the engine turns over and over. No spark while touching plug to head.
With a plug pulled and held against the head I can ground out the ignition coil negative (-) to ground and the plug will spark. I hooked a timing light to it and can see the timing light flash.
I put the plug back in the bike and try to perform the same test and the timing light does not flash.
The ignition coil windings all tested out within spec. But I read a note in the manual that states:

"If the meter reads as specified, the ignition coil windings are probably good. However, if the ignition system still does not perform as it should after all other components have been checked, test replace the coil with one known to be good."

So tonight I will see if there is an easily removable coil form another bike I have that works and see if I can get it to spark.

Any input would be welcome.

[Triple Jim]

I doubt if both coils have failed at the same time. I guess it doesn't hurt to try another one though. What would be really nice would be to try a known good TCI unit.

[Zanrith]

Originally Posted by Triple Jim

I doubt if both coils have failed at the same time. I guess it doesn't hurt to try another one though. What would be really nice would be to try a known good TCI unit.

I have two CDI units both test out fine... but... yes would be great to get one off of a running bike. Anyone in WNY want to give me a hand?

[Triple Jim]

When you're testing, keep in mind that it's not a CDI, it's a TCI. The transistor controlled ignition unit grounds the negative side of the coil intermittently with the positive side supplied by 12v steadily, much like points would. A CDI unit discharges a capacitor into the positive side of the coil primary to make a spark, and the other side remains grounded.

You said "Ignition coil on both positive and negative sides read 12v with the key on. I am getting some sort of signal to the ignition coil when pressing the start button." You should be seeing 12v on the + and - terminals of the coil primary until the TCI unit grounds the - side. If you have an oscilloscope you should be able to see this as a square wave as that terminal is alternately grounded and open-circuited to make sparks. If you don't have a scope, you should see the - coil terminal bouncing from near ground to 12v as you crank.

Again, with a scope you should be able to see a waveform from the pickup coil, but even with a meter set to AC you should see a couple volts. It would be good to find out if that signal is present at the TCI unit's input.

[Zanrith]

Thank you for the information, while searching on this forum and ebay for part the "IC Igniter," as it is called in the service manual, has been referred to as a CDI which is why I am using that terminology.

I do not have an oscilloscope but when I have my multimeter on the ignition coil and hit start the voltage drops. I don't believe it was hitting around 4-6v when cranking before but I was under the assumption that the signal was so fast that the multimeter was not fully zeroing out.

[Triple Jim]

Yes, everyone calls it a CDI. But when you're trying to diagnose a problem it helps to know what you really have.

You might try the "peak hold" function of your meter if it has one. If it's on the coil terminal with 12v on it and you activate "peak hold" and crank it, it should show you the high and low voltages it sees. Just get the low reading before you take power off the coils.

Is there any chance your spark plug wires are cracked and it's sparking, but the sparks are jumping to ground before they get to the plugs? (or something like that)

[Zanrith]

Originally Posted by Triple Jim

You might try the "peak hold" function of your meter if it has one. If it's on the coil terminal with 12v on it and you activate "peak hold" and crank it, it should show you the high and low voltages it sees. Just get the low reading before you take power off the coils.

My meter has a hold button which I think is just for holding the information on the screen and not peak hold but I'll find the manual and see if it works the same way.

Originally Posted by Triple Jim

Is there any chance your spark plug wires are cracked and it's sparking, but the sparks are jumping to ground before they get to the plugs? (or something like that)

I don't see cracks in the plug wires they look to be in good shape.

I slapped a different ignition coil and plug onto the bike last night, from a running bike. I was able to ground out the ignition coil manually and get spark. Attached the negative wire and try to start the bike via the starter and no spark. Bike turns over so nicely it just wish I could find the issue.

Going to explore getting a CDI for a 1995-2005 Ninja 250 because the 2006-2007 have a different part number from Kawasaki, maybe that is our only issue.

[Zanrith]

Originally Posted by Zanrith

Going to explore getting a CDI for a 1995-2005 Ninja 250 because the 2006-2007 have a different part number from Kawasaki, maybe that is our only issue.

I can confirm that a 2006-2007 TCI will work on a 1995-2005 even though they are not the same part number and Kawasaki doesn't say that the 2006-2007 superseded the 1995-2005.

So we did a lot of testing between the two bikes. Without ripping the running one apart.

The difference we stopped that confuses me is the infamous Grey wire! I 100% have the 100Ohm resistor in the key switch on the non running bike.

On the running 2005 when the Grey wire is disconnected from the TCI is reads battery voltage (12.5ish) when plugged into the TCI the voltage on the Grey wire drops to 9.5ish volts.

On the non running bike when plugged in or not it reads battery voltage. I'm not sure what the issue is but I will find it. I am going to take a break and then get back to it.

[Zanrith]

Update: All wires reconnected minus turn signals and rear brake light.

Grey wire shows battery voltage 12v +/-

If I unplug the brown wire that runs with the bundle to the key switch, the voltage of the grey wire drops to 8.8 volts but the engine wont turn over.

Now I need to find a correlation between the brown and grey wire.
Thanks to the diagram at https://faq.ninja250.org/images/a/a4...matic_-_R4.pdf I should be able to find out more.

[Zanrith]

Okay I did some testing last night. With everything plugged together I get battery voltage at the Grey wire. If I unhook the brown wire I get 9.something volts at the Grey wire. I am slowly narrowing this down.

We replaced the junction box with a "new" one because one of the relays was only buzzing and not clicking. I am going to run a full test on the "new" junction box even though I did that before. I am wondering if I have a bad diode allowing power in the incorrect direction.

I also tested the starter solenoid though I believed this to be working. It is wired correctly with B going to the battery and M heading to the starter. B, both sides of the fuse and the white wire out all read the battery voltage. Y/R would jump up when start button was pressed.

[jkv45]

Might be some troubleshooting tips in this thread to help you out (thanks to Triple Jim) -

https://www.ninjette.org/forums/showthread.php?t=414125

[Zanrith]

Originally Posted by jkv45

Might be some troubleshooting tips in this thread to help you out (thanks to Triple Jim) -

https://www.ninjette.org/forums/showthread.php?t=414125

Thanks I took a couple days off to reset on this. I will do all of Triple Jim's tests and more. I will post my results the best I can in this and let ya know what I find and if I find the problem.

[Zanrith]

Okay so... I gave up. I went through Triple Jim's tests and was getting the correct voltage everywhere besides the grey wire giving me 12v. So I went back to the book and I ran tests on all the components. Junction box, TCI, Pick up, Coils I spent 3 days just poking at the bike. FINALLY I gave in. I bought a used wiring harness of ebay and plugged it in. And we have spark.

Now that is all well and good but we have very low compression. I wonder if fuel pouring into the cylinders for all that time caused the rings to go bad. I pulled the engine and we ordered rings and a head gasket. We also are ordering a carb rebuild kit because during our testing the carbs were leaking pretty nicely. We assumed we would need the kit but didn't want to order anything until we got the spark figured out. So basically this bike will be nice and new when we get it all back together.

[Triple Jim]

Carb kits contain incorrect non-OEM jets, so don't use any of those, including the needles. Gaskets and float valves should be OK. Take a looks at this to give you an idea of what needs cleaning:

https://n4mwd.blogspot.com/2013/10/s...-passages.html

[Zanrith]

Originally Posted by Triple Jim

Carb kits contain incorrect non-OEM jets, so don't use any of those, including the needles. Gaskets and float valves should be OK. Take a looks at this to give you an idea of what needs cleaning:

https://n4mwd.blogspot.com/2013/10/s...-passages.html

Thanks Jim,

I've done many carbs throughout the years. I took my calipers to them and made sure they were the same size. Everything matched in sizes. The Jets were the exact same size. Not saying that the jets I pulled out were OEM. Everything is back together and the bike runs.

We had to pull the head and hone the cylinders and put in new rings and rebuild from that point up. We timed it wrong the first time because I didn't take enough time to look up where TDC was. The manual was useless because it had been scanned in and you couldn't make out the picture. And a google search brought us to the wrong information. So after timing it a second time we got it fired up. Now we are hunting the perfect A/F ratio and getting the idle sorted out to be in spec with the manual. Couple more days and this should be on the road.

But what a pain in the arse this project has been from a "It just needs a carb clean" to needing a top end rebuild, wire harness, junction box and then of course the carb cleaning. A simple weekend project turned into so much more. My friend is super excited to ride his bike though and has learned a lot of things that he wanted to know about engines and motorcycles.

With that said I'll have a TCI, Junction Box (once confirmed if it works) and a wiring harness if I can find the issue with it. For sale to try to recoup some costs of this project.

[Triple Jim]

I'm glad you got things working. One tipoff with the jets is whether or not they have the Keihin logo stamped on them.