09-19-2015, 12:04 AM
Shutting off an engine at only a long stop light is not necessary and is probably harmful. If you were in extended stop and go traffic on a hot summer day, then maybe an occasional shut down and restart is OK, but jeez, the oil cooler will handle stop lights.
I have experience with police Harleys and BMWs both the pre- and post cooling fan eras. We ran in city traffic, long stoplights and all, sometimes idling while on traffic stops, slow riding in parades and funerals, etc, and no one around me had engine damage. If we were to be stationary for a long time we would not run the engine but keep the bike "ON" because it had an extra battery and higher rate charging system. IDK if any bike runs hotter than a Harley in July, and we had temperature gauges on the bikes. Do you know what happens for a couple of minutes after you shut the bike down in hot traffic? The temperature actually rises for a short time before it starts to go down. So you may be actually doing more harm to your engine if you shut it down at lights. And what about those restarts after the oil has drained into the sump? Most engine wear occurs at startups.
I have experience with police Harleys and BMWs both the pre- and post cooling fan eras. We ran in city traffic, long stoplights and all, sometimes idling while on traffic stops, slow riding in parades and funerals, etc, and no one around me had engine damage. If we were to be stationary for a long time we would not run the engine but keep the bike "ON" because it had an extra battery and higher rate charging system. IDK if any bike runs hotter than a Harley in July, and we had temperature gauges on the bikes. Do you know what happens for a couple of minutes after you shut the bike down in hot traffic? The temperature actually rises for a short time before it starts to go down. So you may be actually doing more harm to your engine if you shut it down at lights. And what about those restarts after the oil has drained into the sump? Most engine wear occurs at startups.