I have a 2014 Road King, it has only 1600 miles, and at the 1st service at the dealer, 1,000 miles, I asked them to put in:
1. HD Syn 3 for the engine.
2. HD Formula + for transmission and primary.
I am planning to go with:
1. Redline 20-50 for the engine.
2. Redline Shockproof for VTwin Transmission
3. Redline VTwin Primary
The why?
I have noticed that since the change to Syn 3 in the engine, from the regular HD conventional, that my back jug has only went into the "pump air mode" 2 times, so the syn oil is making the engine cooler.
Redline I believe has almost a 500 degree flashpoint rating, so my thoughts are in a oil/air cooled engine, that can't hurt.
Just my humble opinion.
RevRider