For the Rotax 912iS builders, please check the tension of your #4 cylinder exhaust springs (aft left side). We found an exhaust leak at conditional and when removing the pipe, realized there was hardly any tension on the springs. After communicating with Van’s, it sure appears that our EX-00024 was manufactured or designed incorrectly. The only part available to purchase now is EX-00024 REPLACEMENT so there’s something going on here. Anyway, recommend iS fliers make sure the springs are stretched to provide appropriate tension and the attachments are in the correct position. Fly safe! -Jim