My brother has a 1979 yamaha xs400 it ran really good then while he was letting it warm up it died then he restarted it and it died again and hasnt ran since. It is getting gas the spark though is kinda reddish color. I check it is in time. And it doesnt have points it has a pickup so i have ruled points out. I just cant see both coils being bad at the same time but i may be wrong. Hopefully some of you guys can point me in the right direction. thanks

charge battery, it needs a GOOD 12v