2001-2005 Honda TRX250EX Sportrax TRX250EX Factory Service Manual, Page 113Get this manual
CYLINDERPISTONCAMSHAFT PISTON RING INSTALLATION Clean the piston ring grooves thoroughlyApply engine oi to the piston ring outer surfaces and install themNOTE: Do not confuse the top and second rings; the top ring is narrower than the second ring in widthBe careful not to damage the piston and rings during assemblyTo install the oil ring, install the spacer firstthen
TOP RING SECOND RING
SIDE RAIL JJ:JooSPACER SIDE RAIL
install the side railsStagger the ring end gaps 1200 as shownAfter installing the rings, check that they rotate freely