ORIGINAL: DaveG55
Running a nitro engine non-stop for extended periods of time will actually cause less wear than going through repeated start and stop (heat and cool) cycles. But it has to be run at WOT. And it HAS to have a load and it HAS to have cooling. It sounds counter intuitive, but WOT will have less wear on the piston and sleeve. If you ran the engine at idle, even with proper cooling airflow, the piston and sleeve would last no where near 24 hours, only a fraction of it. (prolonged idling will kill any ABC type engine's piston and sleeve regardless of other conditions) The most wear comes from changing conditions in an engine (any engine for that matter) i.e., starting, shutdown, temperature swings, power setting/RPM changes. Constant state running is the least detrimental. And with ABC, ABN, and AAC type tapered bore (ringless) nitro engines, the most longevity will come at wide open throttle with proper cooling and proper HSN setting.