When I bought the Strat I got it with aftermarket pipes and power commander. I don't know if the air filter was replaced as well.
Is there any way for me to know if the filter is stock or aftermarket? Please help.
First off you have to get to it, which involves taking off your tank. Best way to tell is by looking. If it's a K&N then it's obviously aftermarket. I would recommend putting the K&N high performance air filter in if its not.
I used a stool along to the side to rest tank on. That way you don't have to go through the hassle of draining your tank. Here are some great videos that were created on how to remove the tank to get to the air filter.