I bought a bandit 400 a couple of weeks ago and it started and ran fine, one morning would not start. Bought a new ignition pulser and ran fine after that.
Problem is was out riding, everything working fine when suddenly engine just cut out, and had to roll to a stop. Now it will not start, won't even turn over. Any ideas any one?

Check your stand switch is working, or try to bypass it and see if it will start. Will it bump start?

dose the starter motor work if not might be starter solinoid

My bike has a similar issue, but someone told me that most Suzuki's have a key ignition issue. So try this, when turning the key, wiggle and jiggle the key, sometime the ignition is a bit broken.