If you look hard enough, you can find an article supporting any damn answer. I've owned plenty of cars, a motorcycle, a boat, dirt bikes, scooters, go karts, a space ship etc etc. I always let it warm up. No problems. Do I need to? IDK. My FiST, 4 bars and let the RPM's drop, I'm gone. Cool down? Don't beat it before I reach my destination.
-drops the mike-