If you're running a little rich would running a higher octane of gas help that any? Someone once told me that but I do not know whether or not to believe that...

 

No
If you are running a little lean, a higher octane will, to some degree, help with pre-det. More so in a 2-stroke than in a 4-stroke.
A higher octane fuel does not produce Horsepower, only aids in pre-det or pinging.
Depending on your altitude, and assuming it is a stock motor, no mods, you should be very good to run regular unleaded fuel.
Only cure is to jet to the proper altitude at which you do most of your riding.