Please don't leave use hanging, let us know what you found.
If the problem was fixed by adjusting the shims there is something you need to watch out for. Value gaps generally only get smaller for two reasons (there are other reasons but they are outliers generally speaking), and they are both concerning reasons. You could have a value that is starting to stretch, or you could have excessive wear on the value or valve seat mating surfaces. Monitor the valve clearance for a while, if it continues to get smaller I would start more serious investigation. If you catch a stretching valve or damaged valve/seat you can replace the valve/seat fairly cheaply. If the valve breaks it will cause what we call a catastrophic engine failure, much better and cheaper to replace the valve early.
Please don't get scared by this, it's only advice to keep an eye on that valve gap. If no significant change is occurring with the gap then you don't need to do anything, you most likely just had normal wear.
