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Negative Ground Conversion

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I have installed a Sparx 3-phase alternator and Tri Spark ignition with single coil conversion on my Mark III. Although the bike starts and runs well, I'd like to change to a negative ground system. Would this simply be a matter of reversing the polarity of the ignition, charging and battery connections, or would I have to do more? Also, would my warning light assimilator work correctly with a negative ground system?

Thanking anybody who can help in advance...

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Hi There Adlai,

There is a thread I started back in march on page 8 of this Commando forum with a lot of good information. Probably as much as you need. I have stuck with my +ve earth but have taken Al Osbourne's advice and fitted two relays to the headlight. I was loosing 1/2 a volt between the battery and the headlight. I haven't got round to getting rid of the ammeter yet but that's next on my list and will remove about 1 metre of wire that is in the main feed line to the ign switch. Headlight is much better and doesn't dim at tickover now. A relay in the horn circuit with thicker wires to feed it direct from the battery is a noticeable improvement also.

 


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