Would it be inappropriate to cite wikipedia for something trivial in an academic article?
The real question is whether you should cite anything at all. You're not writing an article on golf clubs. You're writing an article on statistics.

Is your example so complex that you need explanations upon explanations about why you're choosing this parameter, and that, etc, and if a reader doesn't know all this then the example is not understandable? It it really that important? Then you're wasting your reader's time with a digression that's largely irrelevant to your scientific work.

Is the example sufficiently simple that to understand it, very vaguely knowing how golf works is sufficient? Then why would you want to cite anything? I don't need a scholarly article to explain that if I were to choose a golf club, I need to consider its length, its weight and so on. It's pretty much common sense. Do I know more than that? No. Do I care? No. Is a statistics article the place to learn about such things? No.