1978 DT125 Wiring Help - Yamaha Forums
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post #1 of 1 Old 05-22-2020, 12:50 PM Thread Starter
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1978 DT125 Wiring Help

Hey Guys,

I picked up a DT125 that some garage mechanic decided to simplify by cutting the entire wiring harness out of. It seems they were trying to run the charge coil straight to the ignition coil. I've spent a week reading through the DT125 service manual and I have been mapping out what is responsible for the ignition circuit. It seems that the coil that provides spark would go through the rectifier (which im missing) and into the battery then to the ignition coil. This has a points style ignition.

Replacing the entire harness and lights is beyond my goal at this point as this is an extra bike. I really want to get it to run because its a cool retro bike. Can anyone familiar with the bikes help me map out what a stand alone wiring system would look like? The charge coil straight to the ignition coil definitely doesn't seem to spark. I have tested the resistance of the coils and I don't think im reading them right so im going to focus on getting the wiring in place for it to work assuming the coils are fine. Points and condenser look like a brand new replacement kit, ignition coil too. I have tested the spark plug in my Kawaki and it lights up like a Christmas tree.

I know the rectifier just converts the current but is that needed for ignition? Does the battery need to amplify the voltage to get a spark?

Cant post attachments because its 2020 and we don't have that technology
Tyler Xtt is offline  
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