Can Mogas cause excessive carbon build up?
Thanks for the helpful replies. There is no mixture control on my installation so leaning not an option. Compression tests before each permit renewal have always been in the mid/high 70s. W100Plus changed regularly so oil not an issue. I have CHT sensors on the rear cylinders. It's possible that an early period of hot running before I developed a technique of reducing power slightly immediately after take-off might have been influential. Apologies to Mogas.