HELP 07 300 Pro No spark

[toothandnail]

I have no spark, I have checked stator ,trigger coil with Ohm meter, they check good.

So it must be CDI box , wrong , new CDI still no spark , rechecked with different meter all close to spec.

I say close because I'm using an analog meter kinda hard to read the 20.x reading all were less than 1 ohm off.

I checked the output of stator and trigger coil, nothing.

What's next ? order new stator and trigger coil??

[jse]

I have no spark, I have checked stator ,trigger coil with Ohm meter, they check good.

So it must be CDI box , wrong , new CDI still no spark , rechecked with different meter all close to spec.

I say close because I'm using an analog meter kinda hard to read the 20.x reading all were less than 1 ohm off.

I checked the output of stator and trigger coil, nothing.

What's next ? order new stator and trigger coil??

The least expensive way is to buy your buddy (who owns the same type bike) a few beers (more beers=quicker "yes" answers) and ask to borrow it. Swap one piece of the system at a time to isolate where the problem is. Don't forget the cheap parts, like the plug cap, as they can stop an engine as quick as the expensive parts.

Jon

[toothandnail]

Problem is nearest simular bike(that I know of) is 2-3 hrs away.

I've done some research , seems I may need to check the blk/wht wire from coil for a break. but wouldn't the stator still output voltage?

[arnoux]

The large black connector plug that connects the CDI to the rest of the wiring harness can also be a place to check. They use the same plug on KTM's and they are always causing issues on those bikes under harsh conditions. Have you had that apart recently?

We have only had it happen once on a GG, but it did take us a while to source the problem.

[toothandnail]

The large black connector plug that connects the CDI to the rest of the wiring harness can also be a place to check. They use the same plug on KTM's and they are always causing issues on those bikes under harsh conditions. Have you had that apart recently?

We have only had it happen once on a GG, but it did take us a while to source the problem.

Yes, I've checked it pretty carefully for any wires that may be loose all seemed good

[pandelboy]

double check that the earth wire ( thin BLK/WHITE) from the cdi plug to the frame aint broken or corroded. this was a big problem on these years as the wire was not long enough and under tension.

[dadof2]

You don't say how you checked the output of the stator and trigger coil. Friend of mine had an 07 250 gasser and it did same as yours. It was trigger coil but he had to buy whole stator and flywheel as they come as matched items.

To check outputs properly you need disconnect stator wires from CDI, remove spark plug and put in a few CCs of oil. Spin the rotor with a power drill at about 450 to 600 RPM and measure the output with an AC voltmeter or better still an oscilloscope (PICO ideal if a local garage has one). Expect about 23 to 30 volts from source coil and 1.5 to 4 volts from trigger coil. If you can get similar bike that is working do same procedure and compare the results. If voltages look OK you can still have a problem because static no load resistance measurement may not be accurate. You can have a poor internal connection on either coil that will prevent full required current flow. To check current flow you need PICO or similar diagnostics equipment.

All the best.

[bigfoot]

Have you tried the voltage regulator? I had this go on both my 04 & 06 bikes. Simple and cheap to replace.

[toothandnail]

IT RUNS!!!

However , I still don't know what the cause was , I was leaning toward the stator or trigger/pickup coil. I ckecked EVERY connection again, 3rd time, they all looked good and clean, still only able to get 4.5v on yellow stator wire & 1.5v on trigger coil. Put it all back together before leaving for work. Decided to check for spark at plug , for the heck of it, SPARK! put plug in started on first kick.

Now I got 10 days to test before a 2 day ride

Dontcha just LOVE elect. problems

[perrin]

I had the same problem on my 06 gas gas 300. It was the earth wire in the CDI unit. The slightest movement at the CDI just breaks the curiut. The wire is just to short and when you remount the CDI the wire moves. I re mounted the CDI then with a pair of long nose pliers pushed the earth wire into the CDI. It move about 1/2 a mm but works every time. Perrin.