From year round riding on my wee (60k)
The slider pins (bolts), pad retaining pins, pad backs and the piston/seals/seal recesses all need attention.
Don't clean the pads and think that'll sort it.
In for a penny, in for a pound.
Or else you'll be stripping it again very soon.
Get a seal kit from we moto, red rubber grease, brake fluid, and a brake bleeder hose/kit and do the job properly.
I found that the brakes needed to be stripped every spring and a remove and clean of pads and pistons, grease sliders in the autumn ready for winter.
Just be glad you don't have a GSX1400 or k1-3 GSXR1000.
The front calipers are 6 pot (12 pistons) splitting the caliper into halves. It's a pain on the arse and is an annual chore regardless of how you ride, keeping it dry or even never riding it!
500miles last year and it still needed a full strip and new disks.