I use to do line clearance , the stick saws we used in the bucket oiled the chain from the hydraulic oil that ran the saw, which ran the bucket. On my own ground saws, I've used vegetable oil with some STP added. Remember you want the oil to stick to the chain, not fly off as it spins. Regular bar oil usually has some Tac or cling additive to help keep the oil on the bar. So if I run any oils other than bar oil , I just add a little stp for cling. Just my 2 cents.