I have the 107 on my Heritage with a Stage 1
I only have about 500 miles on it but this thing feels like it runs real f’ing hot compared to my 103 with the same set up, although the tuner on the 103 is a Power Vision and a Screamim eagle on the Heritage.
The 107 is still running very lean.
Anybody else feeling the heat?

 

More displacement,more heat.

 

Maybe it's the tuner, on my 114 I'm not noticing more heat compared to my past 2014 103. I didn't measure, I don't have a number, just what I feel.
I also think the routing of my rear exhaust header pipe helps with the felt heat on my current bike.

 

The 103 on my night train was definitely hotter (seems to me anyway) than my 107 LR

 

My 114 is running about 260 right now 80 sothing degree weather

 

no different really than all the Harleys we've had in the last 15 years..well maybe some but I don't pay attention to it, as loooooong ago I accepted the fact that I'm choosing to sit on top of a combustion engine that's attached to two wheels

 

Get a multi bike license for the vision. The se tuner will not allow to much change, as it is a licensed epa tuner. Also look into DK Customs tank lift and cooling deflector wings. I am currently using the 1.5 inch lift with the wings, it does work.

 

Now entering my third SoCal summer on the 2018 RGU. At 34k miles, I'd say the stock 107 is noticeably cooler running than the stock 2016 103 FLHTCU it replaced. The 2016 103 on a 95 degree day in steady city traffic would just about blister my right thigh. I don't get this on the 2018 M8.

I recently re-read the Cycle World introductory article from 2016 on the then-new M8. In the article, Kevin Cameron states that HD claims the M8 runs cooler than the 103. I'd have to agree with this. It "feels" cooler to me.

But, that isn't an impression gathered after a short ride on a hot day, but rather an impression created after several summers of riding in all kinds of weather and traffic. And there is the point that I would make for the OP: 500 miles is probably too short a time of riding to develop very firm opinions about engine heat. Or saddle comfort, or tires, or just about anything else. Give yourself lots of time and plenty of miles. First impressions are almost always wrong.

 

yeah, I think in Kevin's interview with the Chief M8 engineer it was stated the exhaust valve ET area was 100 degrees cooler than the TC

 

Go out and sit on your car motor after it comes up to temperature, for comparison.

My 103 with SE255 cams, Jagg oil cooler with fan, and wards head fans, definitely ran hotter than my twin cooled 107 M8. But, my 103 had full catless V&H exhaust, whereas my M8 still has the cat. So, on my M8...my right heel gets hot!