I did try chainsaw oil. I bought a litre from the local agriculural merchants, and a nice oil can to apply it. I found it very stringy and difficult to get it to drop onto the chain which caused me to put too much on. I wiped off the excess as best I could but when I spun the pedals the oil flew off the cassette like sparks from a Catherine wheel, and even after repeated wiping it still happened. I gave up on it in the end as it caused too much mess on the wheel and frame, so if anyone has a good use for chainsaw oil perhaps they could let me know. I am now reverting to light engine oil which I have used for half a century without problem.