Bel ray filter oil... tacky and cheap. and fresh filters everytime. I can make filter go a few weekends by being religious with filter outer wraps.
I use 3M vetrap, cost like a 1.50 a roll and I will put a fresh wrap on the filter after every couple runs or when it looks even a bit dirty. can make your filters go much longer, but more importantly, keep a consistent tune on the motor. As the filter gets dirty, even slightly, it will change the airflow to the carb.