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Discussion Starter · #1 ·
I have a '78 CX and the 7v regulator is inside the gauge cluster housing. I installed a single tach (from a '80 GL I think) in place of the massive gauge cluster on my bike. This new tach only has yellow wire and green wire coming from the bottom side. Looking at my 7v regulator from the '78 I see a yellow, green, and black wire. I know where the yellow ang green go, where does the black one go?
 

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On all the CX's I have had me grubby mitts on

All greens are ground

All blacks are supply wires which come live at ignition on

Only ever seen a single yellow as an output from the 7V regulator

to supply the gauge.



The above is the usual convention unless a PO has decided otherwise
 

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On all the CX's I have had me grubby mitts on

All greens are ground

All blacks are supply wires which come live at ignition on

Only ever seen a single yellow as an output from the 7V regulator

to supply the gauge.



The above is the usual convention unless a PO has decided otherwise




Ditto
 

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Wish I knew Photoshop well enough to do more than the basics. It sure would be a help to produce some new wiring diagrams from the old.



All the diagrams I've ever been able to find have been rather small thus sometimes reading them is in question. I've also seen a few that were in color which helped.
 

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I have a '78 CX and the 7v regulator is inside the gauge cluster housing. I installed a single tach (from a '80 GL I think) in place of the massive gauge cluster on my bike. This new tach only has yellow wire and green wire coming from the bottom side. Looking at my 7v regulator from the '78 I see a yellow, green, and black wire. I know where the yellow ang green go, where does the black one go?
The wires coming from the GL tach are from the temp gauge. The yellow hooks to the yellow from the 7v regulator,, the green/blue hooks to the green/blue wire from the temp sending unit.



The 3 wires coming off the 7v regulator,,yellow is 7 volt output(hooks to the yellow from the tach), the green is ground(hooks to green ground),,and the black is the power into the 7 volt regulator(approx.12 volt when the bike is not running but key is on/ approx.14 volt when the bike is running/ 0 volt when the ignition is off) from the wiring harness
 

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Well maybe ground is the wrong word on this but on the 78 it didn't have a bullet connector. It had a standard connector that I thought hooked to one of the bolts that holds the temp gauge in the assembly. I cant seem to find a picture at the moment but one will show up.
 

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Ok who has a view of the 78 like this. There use to be one that showed the wiring in the headlight/nacelle but I cant find it.













See how it looks like a crimped on eye connector hooks on one side of the temp gauge and the one from the 7 volt on the other.





Edit..... Now that i'm rereading it again I realize we aren't going for stock and the way I read it the bike is only going to have a temp gauge and a tach. I could be wrong but that's the way I'm reading it again. I didn't think the larger gl's had a temp gauge in them.
 

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Discussion Starter · #11 ·
Stitch, you are right, not going for stock here. You are also correct saying the black wire was attached to one of the post bolts holding the temp gauge in the dash.



For the mod I think I will grab a single connector to attach the black wire to the harness from the bike. (I think this will work)



I'm not sure what year GL this tach came from, but it is from a GL and has only a yellow and a green wire coming out of it. I'll be testing it later and will report findings then. I really wanna get the temp gauge hooked up because that damn water pipe gets hot! Not sure if that is normal or not.
 

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I'm not sure what year GL this tach came from, but it is from a GL and has only a yellow and a green wire coming out of it. I'll be testing it later and will report findings then. I really wanna get the temp gauge hooked up because that damn water pipe gets hot! Not sure if that is normal or not.


The engine coolant transfer pipe can get hot but it varies of course depending on the heat cycle it's in.At start up it's cool as no coolant flows until the thermostat opens and the coolant just circulates the engine only until then.

When the thermostat opens of course it starts to flow from the top of the engine,down the rad and out through the bottom and through the engine coolant transfer pipe and around and back via the Water pump.

If you are doing static testing,as I did when researching my Electric Fan conversions,it can get quite hot as there's no air-cooling so the whole engine is reliant on radiated heat and even the frame can get warm and of course the mechanical fan is inefficient.As soon as the bike is on the move and air-cooling comes into it then things level out and you'll most likely find that the pipe is not excessively hot if you have just stopped after a ride.









HTH
 

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