Uh not to turn this into another oil thread ......... but I guess this is what it is sorta. I have done this myself on several different bikes and I think the 15w40 dino Shell oil seems like a better fit for my moto's. IMHO the 5w40 is a little lite and actually my foot thinks the 15w40 shifts better. Last year I rode my GL1800 out to CA and back, 6200 miles in 12 days in extreme heat. There were a couple of days while riding in the mountains in CA. where I use a lot of engine braking instead of my brakes and it was the only time in 50K miles the bike actually used any oil and this trip was down almost 1/2 quart. I checked it before leaving CA and it seemed just a little low but checking it the next morning after arriving home found it this low. It points to me to the fact that the combo of high heat and engine braking needs heaver oil. I also had this happen to me back in 1982 on a CB1000 Honda leaving town running 10w40 and when hitting high heat I could actually smell the bike burning oil. Checking it after a couple of days that trip I found it down quite a bit. That evening I bought 20w50 Castrol and changed out the oil, filter and that stopped the oil usage for the entire trip. Of course the CB1000 was air cooled BTW a really neat bike with the dual range tranny.