1972 Yamaha AT2 wiring help

Found a 72 AT2 in the trash and rebuilding as a project bike with my sons.  Most of the ignition wiring was obviously shot and very poorly rebuilt by someone in the past.  I've rebuilt the motor and I'm at the point of getting this thing some spark.  I purchased a new wiring harness and I'm a bit stumped.  In the picture, the red lead on the left comes from the starter solenoid.  I'm thinking the voltage regulator plugs into that single plug.  The dual red female connector on the right comes from the main switch.  I know one of those connections will be to the fuse holder and back to the battery, but I'm stumped on the other connector.  I NEED HELP!!


Ok these are all just photos of the same diagram it's just a bit hard to read with the glare from the flash so I took multiple photos . (my scanner is on the frits) you might try printing them in color and taping them together to get a readable large print ?? 

These bikes require a battery to run











Edited by BruceD_500

Thanks very much BruceD.  I've never seen these in color before.  I rebuilt the red wiring and now have the engine turning.  Next issue is timing.  I don't have access to a dial gauge so tried a poor man's way.  Stuck a pencil in the cylinder and measured for TDC with a mm ruler.  Rolled it clockwise (BTDC I believe) just shy of 2 mm (1.8 called for in the book).  The points to not open at all at that setting, from one extent of the plate to the other.  No idea what to do here.  It appears to close the circuit about 1/2 in or more BTDC.  It will backfire and run backwards.  Thoughts?

Color wiring diagrams will be a great help, thanks.


Have a problem and you may be able to help.  Last fall when the riding season was over I removed the battery to store inside and charged it off and on during the winter.


Checked with voltmeter and the battery is good, above 12 volts. Put it back on, has good fuse, but when you urn the key nothing, no neutral light, no headlight, horn nothing.


Any clues what I show be looking for?


Thanks, David

A corroded connection or disconnected wire. Pay especially close attention to ground points. Maybe keyswitch.

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