Judging whether or not the clearance opens or closes when hot depends on the bike. Comparing an iron head A10 with other models to justify a supposition about this is pointless. The temperatures in the engine are not uniform, so you can't just draw conclusions based on that. What DOES matter is measurement and conclusions. The one data point I have is that at the extreme, the exhaust valve clearances close up on an Iron head A10. When pushed hard (and I mean 100+ mph), my somewhat tuned motor would open up the exhaust clearances and fire into the pipes. Larger exhaust clearances cured this.
Now, Anji, first of all, what a great looking bike. And they are a joy to ride, aren't they? About the noisy valve gear, some of this may be relative. Be sure to check oil delivery to the top end and your clearances, but it is normal IME for the valve gear to get a bit noisier as the motor warms up. This is because the oil gets much thinner. Just how much noisier is hard to say, but all you can do is check and make sure everything is all right and then just go.
Cheers