2012 Road King Classic. Rode approx. 100 miles on the interstate today. 88/90 air temp. Stock 103 with stock intake and mufflers and a catless headpipe. Factory oil cooler. Using Syn 3 and have 3k miles on bike. Cruise control the whole way at 75mph. When I stopped to take a break I checked the oil temp (HD Digital) and it was reading 257. Never been that high before. Is this normal? Seems hot to me but I know these 103's run hot.

 

My 12 SG's oil (Amsoil) is the same...I'd say it's normal...

 

Many folks believe that so long as you are moving you are cooling especially if you have an oil cooler; that is true to a point. High RPM operations for extended periods of time will significantly raise your oil temp. I would not call your observed oil temp alarmingly or abnormally high for the conditions, but I wouldn't call it particularly favorable either. A "cold" tstat for your factory cooler would be a cheap and easy way to get you down at least 15 degrees

 

Normal........

 

Considering the temps & your basically stock bike with stock ECM lean programming, Id say 257 is about right. Think about what it would be without the oil cooler. Getting a EFI controller & adding a little fuel will help drop the temps & add a few HP to the mix.

 

That's normal and nothing to worry about. You may want to shorten your oil change interval though.
Syn 3 is comprised of 3 different base stocks blended together. They use a group 2 which is conventional,a group 3 which is a hydrocracked conventional and a few drops of a group 4 which is synthetic.
Because of the ratio of conventional in syn 3 it won't resist thermal breakdown as long as a real synthetic like amsoil or red line,so at temps which you are experiencing it will turn the oil into water fairly quickly.
I wouldn't go more than 4000 miles on a conventional which is basically what syn 3 is.
Now I'm not saying any harm will come to your motor nor will it blow up,I'm just throwing it out there.

 

I'm running Mobil 1, an oil cooler, FuelMoto 107 and a PCV with self tuning capabilities. Oh yeah, I'm also running the lower temp thermostat (thanks Jason) Under similar conditions (low 90's and 150 miles of highway riding) my oil temp just after coming off the highway was 212-214 degrees. Change to (a real) synthetic and get a tuner, your engine will thank you for it.

 

I swtiched to Moble 1 vtwin at 500 miles on my 2012 103 ci Fatboy Lo! Thinking of getting Rush slip ons and XIEDS! Would it run good with that set up Heat wise?

 

I run about that with my 106....
Ive seen 270 once or twice and I average a lil under 250.
My stock 96 ran 230 with the Ultra cool cooler going so 250 for you is probably on the high side of "about right".

 

How many miles do you have on it? If it's still breaking in it will run hotter than normal. As you put more miles on it you may see it come down. But it is still in the normal range.