Well, here is the follow up. We changed the pitch and got 5200 static and 5560 dynamic rpm. Still high CHT. We decided to continue with the hose replacement for the ROTAX and had the same results. Next we had the carburators overhauled. No change. We replaced the ignition, because the right o e had failed. No change .next we replaced the thermostat and got slightly better results but noticed that the temperatur dropped, when we switched off the master avionics. We recleaned the ground contacts and got rid of that problem, vut still experienced 230F on the left and 250f on the right, which Lockwood considers to high even in 96F. Any comments?