Rm 125 spark problem

adue59
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adue59
Edited Date/Time 1/26/2012 2:10pm
I just got a 85 Rm 125 from a friend for free i rebuilt the top end to get it running but now it is not getting spark while the plug is in the motor but when it is out and there is no compression it sparks fine. If anybody could give me a clue it would be greatly appreciated this my first time working on a 2-stroke so any input would be great.

Thanks
Aaron
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mosslander
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mosslander 7/18/2009 6:25pm
7/18/2009 6:25pm
clean the plug-hat from coroding rust in the clips and make it tighter for better contact to the plug
adue59
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adue59 7/19/2009 10:32am
7/19/2009 10:32am
i made sure the plug boot connections were clean that didn't help anything. I dont know much about these ignition systems i was wondering what exactly the CDI unit does cause from what i have heard they are prone to going bad. I was also wondering if the problem could be the coil not making a strong enough spark

Please Help
Aaron
mosslander
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mosslander 7/19/2009 10:42am
7/19/2009 10:42am
remeber when the plug is out while testing you need eart contact plug, if you kick the engine around without eart contact you can destroy the CDI unit
adue59
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adue59 7/19/2009 11:56am
7/19/2009 11:56am Edited Date/Time 7/19/2009 11:58am
i don't know what eart is? so if you mean ground contact yes i just ground it out to the top of the head that is how i can tell it has spark. but my question still remains what is the function of the cdi unit?

The Shop

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trick121
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trick121 7/21/2009 3:45pm
7/21/2009 3:45pm
Does the stator plate look corroded?

The first thing guys do is put new stator coils in the early 80's RMs. Do it and your bike will run fine.

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