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‘79 cx500
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Discussion Starter · #1 · (Edited)
I have a 1978 cx500 that the PO removed the dummy lights and temp gauge from.

I like the look of just having a Speedo and tach, and I’ve found stock tachs off other cx500 models which have a built in temp gauge.
Would those be a direct swap? I see that they have 2 wires coming in the bottom to the temp gauge, a green and a yellow wire. My cx500 has one green/blue wire coming from the thermostat housing which I believe is the temp sensor… is this a direct swap? Help with wiring? I believe it’s from a 82 custom or similar…

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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It will be a direct swap, but you'll need a 7v regulator. Take a long look at the wiring diagram in the FSM, and you'll see how it's connected.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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I hadn't really looked at the photos.
A tach from a GL500 (and maybe a n '81 or '82 Custom) will be a direct swap.
 

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i have a good cx500c gauge set i could sell you for super cheap. its a direct swap wiring wise from when i had them on my cx500 standard.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Green is ground.
Yes, you still need the regulator. The temp sensor requires a steady voltage input, and nominal 12v system power varies with engine rpm.
 
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Green is ground.
Yes, you still need the regulator. The temp sensor requires a steady voltage input, and nominal 12v system power varies with engine rpm.
the regulator is built into the custom gauges. you dont need to add it when swapping clusters.

edit: i think the regulator is built in the gauge cluster housing itself, not the gauge. regardless, i have a complete set that worked fine on my standard.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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That's the first I've heard of that. Isn't it mounted below the gauge?
 

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2005 Triumph America
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I have removed the CX Standard gauges and replaced them with CX Deluxe/Custom gauges without any complications. Interchangeable.
 
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