When I (not aphantasic) see something like a bike, I see characteristics of it but I don't imprint the entire bike as a whole. Which means that, were I to draw one, I'd have to re-derive aspects of the bike that I didn't bother to memorize, because they haven't been important to my understanding of bikes. My visualization of the bike would be less precise in the areas that I haven't memorized, like in the precise layout of the frame or location of the seat/pedals or proportions or etc. I assume that someone more familiar with bikes, who has memorized more details of a bike, would be better than I am at drawing a bike.