Originally Posted by AF
It's likely your valves, a lot of Hondas are known for this. They don't seat properly when cold, and by the time the engine heats up and metals expand, it goes away.
If it's really bad a valve adjustment can help a little bit
Thanks for that. It sounds like the valves are being hit from the bottom and top if they are sticking or not seating properly. There are some additives that might help. I just completed a valve adjustment and it's a relatively quiet engine after warmup.