Speedmaster Engine Heat

@Dr. Mark Bohn Welcome to the family. Can't help but i am sure someone will be along soon. Do tap the upload a file button and show us all the bike

 

@Dr. Mark Bohn Real nice bike. Like the fluorescents tee shirt is not bad either. Thanks for sharing the pictures.

 

Heat is an interesting, and very subjective topic.
I have two Bonnevilles, and while they do put off some heat, they are nowhere near as warm as Tiger 900s I've demo'ed, or as my wife's Indian Scout! The Bonnevilles really only get warm while stopped and the fan is on. I personally have no issues while moving, but that's me.
I would consider removing the fork bag to allow maximum airflow. Probably won't help much but at least can say you tried.

 

I have a 2018 Speedmaster. Bought new as a leftover in 2020. Why no one snapped up this pretty baby for two years I can't imagine. Anyhow, I have never noticed any heat issues. I have never even heard the fan kick on. She is decatted.

I installed this oil temp gage that replaces the original oil cap when I first got her. I have never seen it go above 150 degrees F. Not all that hot. You might want to consider investing in one of these. You can monitor the temp and note if any particular condition results in a spike in temp (idling for long periods, flogging her hard in summer heat, taking on steep hills, etc.). As for the coolant. I've never changed it. It's a closed system and I see no need to. Maybe when I hit 10k miles I'll look into a drain, flush and refill.

 

I have a Scrambler 1200 and noticed the fan cuts in at 103 Deg C and it will do so readily in traffic but never has a problem controlling engine temp. Personally I can’t see why the other models using the 1200 twin should run any hotter. The headers on these bikes do radiate a lot of heat being quite large and exposed and not shielded behind bodywork.