I have a Trek 1.2 that has Shimano Sora STI, 9 speed levers. I've only used the bike one season but thinking maybe I should add some lube to the levers. New to brifters so I'm not sure if this is good practice or not. For lube choices (in the house at the moment) I have silicone, wd-40, Boeshield t-9.
What would be the preference,if any, and is it as simple as pulling back on the lever and giving the parts a spray?