More on heat management showing head temp and engine parameters...
Injected Twin Cam High Temperature Idle
The 2006 and later fuel injected Twin Cam engines use a three phase heat management system to reduce engine temperature under extreme conditions. Be aware that a rider with a very hot engine may notice the affects of this three phase heat management system and incorrectly assume an idle problem exists.
Phase 1 - At approximately 320F the ECM will gradually reduce engine idle speed until the engine temperature drops or the engine reaches 800 rpm.
Phase 2 - If engine temperature reaches 338F the ECM richens the air/fuel ratio to provide additional cooling.
Phase 3 - If the engine temperature reaches 356F fuel injector pulses are interrupted. The air drawn in and expelled helps cool the engine further. Since there is no combustion it would be perceived as a misfire. This third stage will only happen when the motorcycle is stationary.
These are head temps as indicated and NOT oil temps
Reference: H-D Owner's Manual.
Injected Twin Cam High Temperature Idle
The 2006 and later fuel injected Twin Cam engines use a three phase heat management system to reduce engine temperature under extreme conditions. Be aware that a rider with a very hot engine may notice the affects of this three phase heat management system and incorrectly assume an idle problem exists.
Phase 1 - At approximately 320F the ECM will gradually reduce engine idle speed until the engine temperature drops or the engine reaches 800 rpm.
Phase 2 - If engine temperature reaches 338F the ECM richens the air/fuel ratio to provide additional cooling.
Phase 3 - If the engine temperature reaches 356F fuel injector pulses are interrupted. The air drawn in and expelled helps cool the engine further. Since there is no combustion it would be perceived as a misfire. This third stage will only happen when the motorcycle is stationary.
These are head temps as indicated and NOT oil temps
Reference: H-D Owner's Manual.
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