Check the timing at idle. I don't recall the timing specs, but if it is firing After TDC, the first section of the exhaust pipes will be glowing. It won't be too bad while running revved up, but idling about town will have the motor cooking. I discovered this when I retarded the tming after installing hot coils and opening up the sparkplug gap. The proper way was to close up the slots so it would not advance as far as stock, but it was late at nite and I had to ride in the morning
You may have an advance that no longer fits tight to the cam, if so, it will slip to a retarded position normally.