The bike is a Hero Honda Splendor Plus, and I've been seeing some fluid on the engine area for a month. Earlier I used to ignore it and wipe it off, but it returns. The bike's mileage has also reduced, which makes me concerned. I assume it would be some kind of oil leakage, because petrol would've evaporated immediately. Didn't see any obvious signs of tube cuts though. Pictures below.
Right side of the vehicle (The engine oil dipstick is tightly lodged, so am sure it couldn't be the engine oil that's splashing out):
Right side view of tubes above:
I know I should show it to a mechanic, but before going there, I wanted to know what could be the probable causes and if it is something I could fix myself. Mechanics here have a habit of exaggerating the cause and overselling.