I want to change the engine oil soon and am not the best for the moped. Harley Davidson Softail Heritage Classic 96 Cui from 2009. At the moment I have the SYN 3 from HD in it and am superior to how it goes on, because the countless opinions on the oil have not brought me any further. I found online the following offers: Amsoil 20W-50 synthetic 1 Gal. = 60,00€ SYN 3 20W-50 partlyynth. 1 Gal. = 80,00€ RevTech MTP 20W-50 synth.1 Gal. = 64,50€ (each with shipping costs) Pr The oils are not so far apart, so the question is now: What is best to recommend ?