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Discussion Starter · #1 · (Edited)
Hi there, looking for some advice to a strange spark issue i've been chasing for the last few days, the symptom is i only get spark when releasing the starter button i done tons of research here / online & performed most of the common recommended checks i.e new battery, good grounds, multi-meter on the coils, pickup etc..

i've narrowed down the issue to the blue and white wire connected to the starter relay which is also linked to kill input (ecu pin 11) & RH handlebar kill switch, If i remove the wire from the starter relay (pin 86) and instead ground the connection i get spark while holding the starter.

I've got a strong feeling its the CDI as i'm seeing 4.96v on the blue & white wire connected to the starter relay I would expect this to be grounded. Is anyone aware or able to test their RS125 to see if they are getting voltage on this wire?

I don't think it's a coil or HT pickup issue as the bike will start fine if i manually inject the starter relay with 12volts or ground the blue / white terminal on the starter relay pin 86

Thankful for any advice! Carl
 

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Discussion Starter · #2 ·
Just an update i've now tried another CDI & Rectifier without any luck... really stumped on this. Thinking of replacing the stator and pickup but the fact it starts fine when jumping to ground would suggest these are working ok... i'm running out of ideas help please
 

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Discussion Starter · #3 ·
For anyone that cares... the issue is fixed and was caused by the starter relay, worked fine when grounded outside of the loom so strange one, new relay installed and sparks fine now
 
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