2005-2006 Honda ATV TRX500FE/FM/TM FourTrax Foreman Factory Service Manual, Page 91Get this manual
LUBRICATION SYSTEM Measure the pump body clearanceSERVICE LIMIT: 0.25 mm (0.010 in)
Remove the oil pump shaft and drive pin, and measure the pump side clearanceSERVICE LIMIT: 0.11 mm (0.004 in)
ASSEMBLY
Dip all parts in clean engine oilInstall the outer and inner rotors into the pump bodyInstall the drive pin into the pump shaft, and install the shaft into the inner rotor and pump body by aligning the drive pin with the inner rotor grooveOUTER ROTOR PUMP SHAFT