This is from Australia . I have been using a OPS 67 since 1989 and have only changed the brand of exhaust coupler from the factory piece to the thick wall Aerotrend silicon . I also drill out the water nipples to 2mm on the watercooled exhaust adaptor p / n 6887 . I would still be using this motor except for SOME KIND HEARTED PERSON who was in my house without my knowledge and took 4 OPS 67 , 1 OPS 65 , 1 OPS 80 , 1 OPS 90 and a Mathe 35CC motor . Didn't mean to steal your post .