Binding brakes - Front caliper pots not going back in easily

[darrsi]

You mustn't forget that some of the rain we get is nothing short of toxic, which is why sometimes i'll go out to my bike at work after a downpour and it'll be covered in a dusty residue.
This will also find its way to the calipers so unless you plaster the red rubber grease on the outer pistons like i do there is that chance it can gradually create a bit of friction.
Changing the standard brake lines is a huge plus anyway so i'd start by sorting them out first.