I might be about to get dogpiled for this, but on inexpensive bikes, I just bend the lever back, shoot the innards with WD40, and wipe off any excess.

Surely that's not as good as disassembling everything and relubing with a longer-lasting lube. But it still works about 100x better than having a bunch of gummy or dusty crud in there, and it takes 30 seconds. Never had a problem with them gumming back up again quickly, but I figure I can always just re-blast it with WD40 or do the whole disassemble-clean-relube process later.

Not sure if this is appropriate for your bike, just sharing my experiences.