How to know primer is ready motorcycle fairing painting?

it feels smooth but I can see a couple spots were it looks ripply like in grooves but if i sand much more it will sand the primer away I was told not to use to many coats of primer as it will crack and stuff considering the motorcycle fairing will flex over time

cant really get any good pics of the wavy looking thing. Just think of wadding a ball of aluminum foil up and looking at that. Then tone it down to like a smooth looking ripple that you can see but not feel that's what it looks like just little spots tho nothing extreme.

and there are a couple spots around edges and corners were the black abs plastic is showing will that show through the white and yellow?

there will be a white sealer then a yellow 2008 Nissan xterra adding some red to it to give it a more redder look using PPG stuff in a body shop so airgun oven all the good stuff.

Sand the bad spots smooth, if you need to spot in more primer that's fine. The sealer should even everything out so don't worry about a couple of spots that break through. Any raw plastic needs adhesion promoter, and should have had that before primer if it was all down to plastic to begin with.