Honda CRF450R Owner's Manual page 45

Piston Installation
Place clean shop towels in the crankcase to keep the
piston pin clips from falling into the crankcase.
Apply molybdenum disulfide oil (a mixture of 1/2 en-
gine oil and 1/2 molybdenum disulfide grease (con-
taining more than 3% molybdenum disulfide additive))
to the connecting rod small end.
Install the piston with the "IN" mark and/or the large
valve recesses facing the intake side of the engine.
Apply flesh engine oil to the piston pin.
Install the piston pin and new piston pin clips.
CAUTION:
Use new pin clips. Never reuse old clips.
•
• Do not let the clips fall into the crankcase.
• Do not align the piston pin clip end gap with the
piston cut-out.
IN
(1) PISTON (2) "IN" MARK
(3) LARGE VALVE RECESSES
(4) PISTON PIN (5) PISTON PIN CLIP
(6) CUT-OUT
Cylinder Installation
Clean off any gasket material from the gasket surface
of the crankcase, being careful not to let any material
fall into the crankcase.
NOTE:
• Be careful not to remove any metal from the gasket
surface.
Remove the shop towel. Do not let any gasket debris
fall into the crankcase.
Install cylinder gasket, A dowel Pins and B dowel pin.
CAUTION:
• Do not let the dowel pins fall into the crankcase.
(1) CYLINDER GASKET
(2) A DOWEL PINS
(3) B DOWEL PIN
Clean the any gasket material off the cylinder.
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