If re-tuning the engine doesn't solve your problem then you should change your loose fitting gasket. Actually even if the re-tune does solve your problem you should change your gaskets... and springs. Make sure you get the right style of gasket for your engine. Picco based engines use a different gasket than everyone else as far as i know. They don't have an internal rib like the others. Also, some gaskets are garbage. For Picco based engines i like Picco and Reds gaskets. For the other style gaskets, I like Protek high temp gaskets or Novarossi. Yes they cost more, but are better. Seal better. Last longer. Protek springs are just fine too.