I know, I know, but I just trying to rule out oil being a factor, as I don't have the experience to know different. Changed the oil the other day for motul v300 15W50. Bike feels like its missing some oomph in the midrange and I have to rotate the throttle a lot more that I remember. I checked the last dealer service and they used 10W40. Manual recommends 15w50 but says you can use either. What does 15W50 mean anyway, i'm now imagining its somehow 'gloopier', its probably not though.
The last number (40,50) tells you how thick it is when hot. Think of it like this, put the hot oil in a can with a small hole in it. If it is thick oil it will take 50 seconds to all drain out. Now do the same with the other oil and it will take 40 seconds to drain out because it is thinner. This is a very simplified explanation. Thicker is not always better as it takes longer to circulate and puts more strain on things, that is why if your blood is too thick then your blood pressure will be high and your doctor will give you some horrible pills to eat.
Thanks for the explanation. So '50' is 'hot viscosity' & higher being more viscous. Question is if its something you can feel engine-wise? And what does the lower number represent?
It isn't overfilled is it mate, that's the only thing I can think might cause lack of power, because the oil is getting pumped up behind the Pistons and past them
In my opinion you can feel a difference between */40 and */50, the 50 is thicker. I use 5/40 in all of my bikes including the 848 but I live in a warm place and have the benefit of many years in the aircraft industry working with oils. You must use what you are happy with but just because a dealer recommends a particular brand, do not let that influence you as the dealer will use whatever he makes the most profit on, after all every business only exists to make money.
It feels like before I disabled the exhaust valve, but more even throughout the rev range, tight. Its not over filled, so it might be the valve stuck at a half open position... will need to investigate further. Only used 15W50 because its what Ducati recommends. God knows what kuck bulk oil the dealer put in.
They always will for light aircraft. Most of them are flat fours now, but even on old ones people still tend to use thoroughly modern oils. I use 5/40 in my aircraft too, and that is a very expensive engine.
These days there are no such thing as bad modern oils. If you wanted to choose between manufacturers then you would be lucky to find one that is 0.5% better than another. Your engine is more likely to suffer a catastrophic oil related failure due to not tightening up the sump plug or oil filter than it is from a poor oil selection.
