A few months back I made a custom leak down tester for Jason(UK) and here are some photos that I received and wanted to share. Jason owns a Banshee motor with Athena 421cc cylinders and used to have constant seizures on LH cylinder and needed to verify that there is no air leakage on crankcases, oil seals etc. Hi Nick, You did me a special leak down tester for my 421cc Athena Banshee last October. Your kit fitted perfectly and I had zero leakage - actually gaining a bit of pressure after 7 minutes due to a little air bleeding back from the second cylinder through the labyrinth seal after I had taken the pressure a little over 5psi and then used the needle valve to set it to 5psi exactly. Thanks again - I am delighted. Jason And here is Jason's bike.