There is a lot going on between pressing the starter button and the engine starting. Get yourself a Service Manual and look at the wiring and components in the ignition system. Your motorcycle should be a Kawasaki rather then the Yamaha category you put it in. Details matter, I'll move it and edit the question to reflect.
https://www.google.com/search?q=988+kawasaki+750+ltd+service+manual
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Check power connections and relays ---What is issue / not turning over --slow turning - not starting etc generic answer load test starter may be bad new doesn't mean free from defects - connections are clean and no damage bolted correctly
See if it is coming from the rocker cover above it. If not, it is oil off the cylinder bore that is seeping out instead of being burned. Replace the exhaust gasket.
https://kawasaki.ph/motorcycles/barako-ii/barako-ii/
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Ideal spark plug gap varies slightly depending on brand - check the online application catalogue for the brand of plug fitted to your bike and the recommended gap will be found in the relevant entry.