2006 Honda TRX680 Rincon Factory Service Manual, Page 96Get this manual
MAINTENANCE
BRAKE FLUID
Do not mix different types of fluid, as they may not be compatible with each other Do not allow foreign material to enter the system when filling the reservoir Avoid spilling fluid on painted, plastic or rubber partsPlace rag over these parts whenever the system is servicedNOTE When the fluid level is low, check the brake pads for wear (page 4-18) low fluid level may be due to worn brake shoes or padsIf the brake pads are worn, the caliper piston is pushed out, and this causes low reservoir levelIf the brake pads are not worn and the fluid level is low, check entire system for leaks (page 4-19)