I have an issue with my 2000 225 johnson. I am only able to turn 5000 rpms. Its on a 99 javelin r20. The engine was built approx 3 yrs ago, and I had the jack 6 inch jackplate put on it then. Engine is setting 3.5 inches below pad and running a 25 tempest per todd morgan. No matter what prop I run in the 25 or 26 pitch, 5000 rpms is the best I see. I replaced the vro/fuel pump, new plugs, roller on throttle. I have checked that all the carbs are opening up all the way. It runs like a champ but want break 5000. I have done a leak down and compression check with almost perfect results. Every once in a while, when I press the gas comming out of the hole it will have a slight stumble but picks up and goes. I notice no miss at all. I have ran seafoam through the last 5 tanks of gas. What am I missing? I also put a timming light on each cyclinder going across the lake to see if maybe I am dropping spark. My problem is that the timming light cuts off on all the cyclinders over 3500 rpms. I even tried another gun. What am I missing? Thanks in advance.