1974 st70 do you need a battery connected to get a spark

1974 st70 will I need a battery connected to get a spark.

H there,i in theary the answer is no because the ST gets its spark from the magneto but the bike when running will be trying to recharge the battery meaning you'll have two live wires were the battery was which could short something out so it's best to run it with a battery because the lights or anything else wil not workl and it'll probably keep cutting out .