Yes, the timing curve is built in. I recently installed a 550 GPz motor in my KZ 550A frame. An old (45-50 year old) KAW mechanic ( I'm 57) told me that the 550A IC igniter would retard the timing off idle. The GPz igniter must be wired into the A frame harness ignition coil wires and pick up coils.
The URL below offers manuals online. An '85 GPz manual is listed. I tried to download one for myself but the web site is having server troubles. I haven't tried today but will when I log out here. RepairManualClub.com
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