M1, 15W-50 is always a good all around choice. With a nice robust HTHS of 4.5, it holds up to the heat. It also flows quite well during "cool" starts.
I was joking. Just a jab at Kawasaki and Yamaha (I am a Honda boy).
I know different engine designs have different requirements. But as I said, I do find the chart odd in the cutoff temp for a xw-40 oil.
What you were seeing with engine temp rising and oil pressure dropping, was the oil getting hot and thinning out. Thinner oil will give less oil pressure than thicker oil all else equal in the same engine. There is no inherent danger as long as oil pressure is within specs, but that it what you were experiencing. Post #6 is my experience with it in my bike.We need to ask the viscosity of the HOT oil. Decades ago I drive a semi fora major corporation from San Francisco to the Los Angeles basin . climbing the Grape vine hill with a max load, it was always a max load , on mild days the temp and oil pressure gauges would barely move going up the hill on the scorching hot days the temps would climb and the oil pressure would drop. Can the bike be run hard enough and long enough to get really hot? I been thinking which is a bad thing to do.
10W-30 is specified for both of my motorcycles for all temperature ranges. I run 10W-30 in the 700 for local commuting. The bike does not have any gauges for temperature. Ignorance is bliss, I guess.And here’s silly old me running 10W30 even when it’s 115 - 120 out. That’s all my owner’s manual specifies, though, regardless of ambient temp.
(-:
This year, for the first time, I put a quart of Red Line’s 10W40 in along with the 10W30.
OP, I’d at least seriously consider a 20W50 for the service you outline, given the way the manual looks.
10W-30 is specified for both of my motorcycles for all temperature ranges.