I'm not familiar with Honda quads anymore. Are they hydraulic or cable? If they are cable, go to any atv store and get some cable lube and a cable luber. Or they could be seized if the machine has seen lots of moisture and put away wet
Disc or drum brakes and front or rear? If drum you need to disassemble clean everything real well, and likely replace or at least clean and lube really well the bushing where the cam goes through the backing plate for the brakes. This gets gummed up bad all the time.