Ironhead Tachometer wiring/speedo hookup

[Darren Rahilly]

Hi all. My bike is a 1980 xlh 1000 sportster that came to me with no tach or speedo. Here is a picture of the set I bought, as well as the wires hanging out of the tach. https://imgur.com/gallery/EC68qhD
My question is- how to wire it up? Does it need power from the battery or just from the coil? Or both? I thought it was a cable that went to the right side of the engine but I’ve read that it gets wired to one of the two posts on the coil? Anyone know how to go about this?

[Racepres]

All of my Ironheads use a Cable drive Tach...But.. to run Electronic tach (usually for Shovelhead FX) the Pink wire counts triggers..Opposite the White wire on Coil..
Orange wires are Accessory on Harleys...12V when Key is on.
White wires that are Not to the Coil...like the one you see on yer tach, are for High beams..so that high beam indicator in yer tach, should light when applied to 12v.
Odd that I looking for a Ground...and do Not see one...tho those gauges are usually fed a Ground.. and I need to study red???? I'm out on Red!!!!

Silly Me...I checked...on Japanese Gauges...Red is for the Gauge Illumination...Lights..
Now..in awhile I will ensure the Black is within the Gauge mount..which I remember it being!!

Betting that right now yer wishing you woulda stuck with the Stock mechanical tach!!! I have one of those here also!!!

[Darren Rahilly]

Originally Posted by Racepres

All of my Ironheads use a Cable drive Tach...But.. to run Electronic tach (usually for Shovelhead FX) the Pink wire counts triggers..Opposite the White wire on Coil..
Orange wires are Accessory on Harleys...12V when Key is on.
White wires that are Not to the Coil...like the one you see on yer tach, are for High beams..so that high beam indicator in yer tach, should light when applied to 12v.
Odd that I looking for a Ground...and do Not see one...tho those gauges are usually fed a Ground.. and I need to study red???? I'm out on Red!!!!

Silly Me...I checked...on Japanese Gauges...Red is for the Gauge Illumination...Lights..
Now..in awhile I will ensure the Black is within the Gauge mount..which I remember it being!!

Betting that right now yer wishing you woulda stuck with the Stock mechanical tach!!! I have one of those here also!!!

You do??? I already have a cable! Let’s talk, brudda

[Racepres]

will PM ya

[BigMek]

The '80 did originally come with a mechanical tach. Check out the wiring diagram for the '81 if you want to use the electric tach: http://sportsterpedia.com/lib/exe/fe...hippysmack.png

Both gauges ground through their housings, so no extra ground wire going anywhere.