It does sound like your running on the lean side.

Here's simple test, fire up the heli, hover or fly around for a few minutes and land and shut down. Put your finger on the back plate of the engine. If you can't hold it there for atleast 3 seconds before it becomes too hot, then your running too lean and need to richen up the main needle a click or 2 at a time until you can.

If you can hold it there longer than 3 seconds or its actually cool to the touch then your running rich. The engine produces less power but will last longer.