2006 Honda TRX680 Rincon Factory Service Manual, Page 206Get this manual
CYLINDER HEADVALVECAMSHAFT TOOLS Valve spring compressor 07757-0010000 Valve guide driver, 5.5 mm 07742-0010100 Valve guide reamer, 5.5 mm 07984-2000001
or 07984-200000D (U.S.Aonly) Valve seat cutter, 35 mm (45 INEX) 07780-0010400 Flat cutter, 38.5 mm (32 IN) 07780-0012400 Flat cutter, 35 mm (32 EX) 07780-0012300
or equivalent commercially available in U.S.AInterior cutter, 34 mm (60 INEX) 07780-0014700