QuestionQUESTION: I'm restoring a 1979 Honda cm185t Twinstar. I was originally going to do everything original but some parts are a pain to find. I think it would be easier over all to switch from a 6 volt to a 12 volt system. I have changed the battery and the rectifier to http://www.regulatorrectifier.com/catalog/1960-1979-Honda-Twin-star-CM185-Twinst which is 6 or 12 volt. My question pertains to the coil. Will any 12 volt twin lead coil that matches my bolt pattern work? Also, do I have to change my stator and rotor? I originally thought all I would have to switch to 12 volt would be: obviously all the lights, battery, rectifier, and coil but now I'm not sure. Please let me know all you can. Thanks
ANSWER: You will have to use a 12v coil that is matched to the ignition system. Coils for points/condenser ignitions have a different resistance value than those for 12v or CDI ignitions.
Look at something from an early Goldwing with points ignition system or one of the 350-750 coils that have long enough leads to reach the plugs.
If you want 12v from the charging system you will have to use a different stator, as well. Probably something from a Rebel 250 might work. Anything that was running on 6v before needs to be changed out.
Bill Silver
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QUESTION: I'm still having trouble finding a compatible 12 volt ignition coil. Do you know a specific bike model of one that would work? And to recap...battery, lights, coil, stator, rectifier are the only things I need to change to switch from 6 volt to 12 volt?
Answerhttp://www.dynaonline.com/skins/Default.aspx They can supply you with a coil that works with points and condenser ignition systems.
The horn is 6v, but they can usually withstand brief usage with 12v feed. Should be REALLY loud now.
Bill Silver
