I have a 2020 Royal enfield interceptor 650, and interested in some options on oil. I've owned a good number of bikes, mostly high dollar sport bike stuff. This enfield has the nicest shifting transmission I've ever felt, up until I reach 300-500 miles, and it starts to feel not as good. Especially if you're going from 2-3 gear, and back down to 1 in the city. Sometimes it doesn't wanna go back to first. That's most likely from it being 90 degrees out, an air cooled motor and going stop lights to stop light ? Changed the oil and did the valves at 500 miles, used maxima 10w-50 pro plus+ (Had it on my shelf). The shifting went downhill around 500 miles, and changed to motul 10w-50 4t semi synthetic (had it on my shelf) The shifting feel lasted 300 miles on that oil, but ran it 1,800 miles and changed it out for the same thing as I had more on hand. The bike does call for a full synthetic and 6,000 mile intervals. I couldn't imagine how it would shift at 6k without an oil change. It's currently summer in my region, so 75-90+ degrees and the occasional few random 55-60ish degree mornings. Considering just going with Mobil 1 v twin 20w-50 but afraid that might be too thick? These bikes have a 3 year unlimited mileage warranty. I would hate to mess that up by switching viscosities. . . Any recommendations for a better quality oil?