Motorcycle Repair: Sticking Rear Disc brake on 1980 Honda, honda cb 900, honda cb 900 custom

Question
Chris:
I have a 1980 Honda CB 900 Custom with 26000 miles. After storing in a unheated garage for the winter, about half the time my rear disc brake doesn't fully release after applying the brake. It will drag slightly causing the disc to heat up. If I tap the rear caliper with a hammer, the brake releases fully. What do I need to do and is this an expensive fix?
Thanks.

Answer
Hi Mark.

No, it isn't an expensive fix, but you will need to rebuild the caliper.

It sounds like you have something in there hanging up.  Possibly a small bit of the fluid turned solid or gummy or the rubber has stiffened up or dried out.  A good rebuild should fix it.

Good luck and ride safe.
FALCON