Now if this smelled like Castor oil I would have it burning day and night. I absolutely love the smell that came from the race cars of the 50's. I can still smell Jack Brabhams tiny little Cooper at the hill-climb at Hepburn Springs when I was 8 years old. or others at Fisherman's Bend or various speedway tracks.
In the UK, where Castrol R is still available, some people from the same old school tip a bit in the fuel tank of there bikes for that special scent. Not compatible with mineral oil so can't use too much.