Changed oil today in the Can Am and for the first time used Motul 7100.
Not only is it red, and shows up nicely on dipstick, but it smells
terrific! All I could do to keep from patting a little on my face!
Yes, the 300V stuff smells like bananas. RLI smells sweet too. Common thing with esters. I once asked my brother, a chemist, and he wrote:
Most “essential oils” are esters, including banana oil (isopentyl acetate). However, I don’t think your motor oil contains banana oil in any appreciable quantity. One of the most striking features of aroma chemistry is that most flavors and aromas are produced by extremely complex mixtures, rather than one or two particular compounds. Nineteen important compounds have been identified in “coffee” aroma, for example. Moreover, some of the same individual components of those mixtures are found in many, totally different aromas. For example, the primary constituent in “banana” aroma is also the primary constituent in “pear” aroma, even thought those two smell nothing alike. Lastly, the concentration of an aroma compound in a mixture can affect how that compound is perceived, smelling one way at low concentrations and another way at high concentrations.
tl;dr aroma chemistry is very complicated
Your brother is right on.
Last spring I worked up 15 gallons of 15W40 for the Ladies miniature Sprint Cars 1.4L engines.
I put some Lilac and Cinnamon odorant in it and the ladies went gaga.
Odorant chemistry for soluble oils is much different than for food and personal care items.