Igntition wiring question ?

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pearljam724
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Igntition wiring question ?

Post by pearljam724 »

Does anyone know what the red and orange wires operate or connect to ? The two wires not connected to the green connector in the picture.
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Alan H
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Re: Igntition wiring question ?

Post by Alan H »

Red from 20A fuse, orange to light switch and pass switch.
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pearljam724
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Re: Igntition wiring question ?

Post by pearljam724 »

Thank you. How is it that there is an aftermarket ignition sold in the U.k. that does not include those 2 wires and they are only 4 wire pins with a connector ? I purchased one of those aftermarket ignitions for my 750 restoration. Even though the wiring is cheap and extremely smaller in gauge, it works fine. Once I had the bike finished back in November the gear indicator would not light up. I haven't had the time since then to do a good evaluation. But, was wondering if those 2 ignition wires were related to that issue ? Now, I see that they are not. But, why do my headlights turn off or on if the orange wire is for the light switch, when I don't have that orange wire on the new ignition ?
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Suzsmokeyallan
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Re: Igntition wiring question ?

Post by Suzsmokeyallan »

For some reason the GT750 only used a four wire system, this means ALL the power passing through the ignition switch crosses two little square contacts on the switch plate thereby joining the red to the orange wire inside the switch for "on".
The brown wire is park and the grey wire is the instrument lights on all the switches, turned on inside the ignition switch, taking power from the red terminal contact, according to how the switch is turned. The 380 and 550 have a pair of switched contacts, hence two reds and two oranges along with the brown and grey wires.
I had mentioned this in the electrical section where I altered the 750 harness to use the 380/550 switch with a pair of separate switched contacts as well. In my system one set of the paired contacts is running the light circuit and the other set is running the ignition and charging circuit.
The reason for all of this is to spread the load from the battery between the switched contacts so they don't become overloaded.
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Alan H
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Re: Igntition wiring question ?

Post by Alan H »

The earlier drawing was the 550 - seeing the 6 wire switch, I assumed that was what it was for, this one is the 750.
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pearljam724
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Re: Igntition wiring question ?

Post by pearljam724 »

Thanks, to the both of you for clearing that up. So, it's safe to say that my 750 is still protected with a fuse if of course it's installed. Which it is, even though I have no extra red wire on the ignition as mentioned earlier ? I never noticed those two extra wires being present or not on the 750. Until recently, when I was cleaning my 550 ignition. Which has now been explained.
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yeadon_m
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Re: Igntition wiring question ?

Post by yeadon_m »

I had a 4 wire aftermarket ignition switch on my 750B, and as you say the conductors (possibly the switch contacts also) were under sized for the load. Mine became hot and the wires in the headlamp shell unacceptably hot when riding with lights on. I chucked it away and fitted a Suzuki switch, all was well.
I have no idea why the 380/550 used the 6 wire system yet the 750 only 4 wires. The former seems a better design as Allan notes.
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Coyote
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Re: Igntition wiring question ?

Post by Coyote »

The single plug 4 wire switch can be used on any if the GT's. In the case of the 550 and 380, the orange and red wires must be externally connected as they no longer run through the switch like the 6 wire switch. Indicated by the blue lines in this illustration.

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