That’s really subjective. Carbs, and in particular pancakes would spike my blood sugar very quickly and I doubt they would stay in my stomach very long. I would probably eat and go, but as I said your mileage may vary.
I would be careful not to wait too long. Again when I (rarely) eat pancakes for breakfast, I’d be VERY hungry after not even a couple hours (due to sugar tanking in response to insuline).
For me, before a long ride (like century) I make sure to get some eggs/bacon (fats) and oatmeal, slows absorption and long lasting energy without sugar bonk. But, I repeat myself, we’re all different, so find what works for you.