Just curious here! When you talk about a dealer, are you referring to an S&S dealer or a HD dealer?
Has anyone checked to make sure the oil lines are correctly installed? Is the engine sumping?
Sumping could cause excessive heat buildup.
This crate engine, does it have the S&S exclusive gear type oil pump or is it the HD georotor type.
What type of tuner is on the bike? Who tuned it?
A LC style motor properly tuned for a reasonable AFR, and not sumping, should run around 200 degrees, even on hot days.
There may be a couple of HD dealers out there that could tune this 124, but I've never seen one I would trust to tune a bicycle.
My carbed T124HC engine has never ran above 195 degrees on the highway, regardless of ambient temps (well over 100 degrees). I did see it get up to 235 one day on the bridge at the Sioux, sitting in traffic for almost 2hrs. It takes 20-30 miles at highway speeds to get oil temps to 190 on 90 degree days.
You need to find a competent tuner, and someone who understands sumping and the S&S systems.
fwiw twinotter