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Discussion Starter · #1 ·
Recently i broke down and once recovered and i was home i found there was no spark but before this bike was running perfect, And found i had a bad stator ive had it rewound put bike back together and im still not getting a spark.

So far ive tried, stator rewind.
tested the coil inc the ht lead ( following youtube video's)
Removed kill switch

When i try and kick the bike over the lights come on and the screen turns on.

ive tried finding videos of how to test the electrics but i have no idea if the stator is even putting out enough power for the spark plug.

Im very new to KTM's and going into bikes this far, Any help would be greatly appreciated.
 

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Lemon drizzle or carrot?
 
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When you say bad stator, what you mean by that? Was it totally fucked? Or slightly different readings compared to what you should get? Out of interest what was the price to get stator rewound?

Um.. have you tried the rectifier? Checked all the earths?
 

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Discussion Starter · #5 ·
The stator was shorting to earth (which im assuming was what stopped the plug sparking) i was getting a small amount of power from it before. it was £120 for a complete rewind. ive checked all earth unplugged every thing and cleaned the connections. I dont know how to check the R/rectifier
 

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you don't need the rectifier for a spark
 
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Discussion Starter · #7 ·
iv ejust done a ohms test on the spark pulse generator and its higher then recomended almost double could this be the problem?
 

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The stator on your bike can be considered as four separate coils.

1. Red and Green wires - the pulser coil
2. Red/Black and Red/White wires - source coil
3. Yellow and earth - AC power to voltage regulator for lights
4. White and earth - AC power to rectifier to feed capacitor for horn and indicators.

The Regulator and Rectifier are in one box - the regulator/rectifier.

To run the bike the source coil provides voltage to charge the CDi and the Pulser coil tells the CDI when to send the voltage to the HT coil. The HT coil increases the voltage and sends it to the spark plug. The Yellow and white wires and the Reg/Rect don't have anything to do with the bike running (or not).

Keep the kill button disconnected.
Test for a spark with the plug cap removed. If the core looks bad cut the end off the lead to clean it up (not so much that it doesn't reach afterwards). If that sparks reconnect the cap and try again.

Disconnect the stator and connect the multi-meter to the source coil wires. Take the spark plug out and switch the meter to AC (20V). Kick the bike over fast and you should get a reading of 15V upwards. If you do then the source coil is most likely good.

Do the same with the Pulser coil and you'll get just a couple of volts (it's a tiny coil) but if that works the chances are it's ok. The pulser was probably tested when it was rewound, maybe worth calling them to ask.

If they work the next check is the other end of the loom at the CDI plug. Same test, same wires.

If it looks good there you've proved the stator, flywheel and loom are good. CDI, HT coil, HT lead, plug cap and spark plug are all that's left. Forget testing the CDI, all you can do is make sure the connections are good and then replace it with a known good one and see what happens.

Testing resistance is good if you know your meter is accurate but some of the readings you're looking for are quite low and a low quality meter will struggle.

When you figure out the problem re-connect the kill switch.
 

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Discussion Starter · #9 ·
Thanks for the reply, il have to wait to try that now as a friend (who was trying to help) manage to snap the plate that the stator attaches to and i now have to try and source a new one.
 

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I had this once on my bike, my stator fucked up and fucked up my cdi. Actually 2 cdi's. Tried mates cdi on my bike and it worked so ordered a new one, within 10 minutes that went too. Checked my stator and 2 of the wires had been cut through with the bit that spins inside the stator. Replaced stator, changed cdi for a 300 one and away it went.
 

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Discussion Starter · #11 ·
Hope its not my cdi but so far everything is pointing towards it. I looked into a new stator and found that the stator recomended for my bike doesnt have the same wires, mine has a block with 4 wires and 2 other wires but the standered one doesnt have the 2 extra ones, Its almost like its almost a mix n match bike
 

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Hope its not my cdi but so far everything is pointing towards it. I looked into a new stator and found that the stator recomended for my bike doesnt have the same wires, mine has a block with 4 wires and 2 other wires but the standered one doesnt have the 2 extra ones, Its almost like its almost a mix n match bike
The EXC has 6 wires, the SX has 4 wires.
 

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Discussion Starter · #13 ·
Brilliant thanks for the reply's. one more question if ive had my stator rewound would it be fine to use now and to order a new cdi?
 

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I wouldnt order a new CDI yet, they're not cheap for a brand new one and if it turns out it is your CDI put a wanted thread up on here or check ebay. Your best bet is here or ebay, much much cheaper than buying new. I got both mine from members of this forum for roughly £70. Do you know anyone who you could borrow a cdi off to try on your bike before you go buying one?
 

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Discussion Starter · #15 ·
Already order a new CDI, been trying to replace old with new when it needs it. is there any chance the rewound stator causing damage to the new CDI?
 

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Discussion Starter · #16 ·
Just and update new cdi turned up and friend fixed the stator and bike seems to be running prefectly again. going for a test ride in moment.

Thanks for every ones help.
 

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Thanks for the update, this helps me diagnose my bike as well as there is quite a lot of information contained within this thread. My stator only has 2 pairs of 4 wires as well.
 
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