Honda 2009 CRF450X Owner's Manual & Competition Handbook page 86

Piston/Piston Rings/Piston Pin
Piston Installation
1. Place clean shop towels over the crankcase
opening to keep the piston pin clips from
falling into the crankcase.
2. Apply molybdenum disulfide oil (a mixture of
1/2 engine oil and 1/2 molybdenum disulfide
grease containing more than 3% molybdenum
disulfide additive) to the connecting rod small
end inner surface.
3. Install the piston (1) with the "IN" mark (2)
and/or the large valve recesses (3) facing the
intake side of the engine.
4. Apply engine oil to the piston pin (4) outer
surface.
5. Apply engine oil to the piston outer surface
and piston pin hole inner surface.
Install the piston pin and new piston pin clips
(5).
NOTICE
Use new piston pin clips. Never reuse old piston
pin clips.
Do not let the piston pin clips fall into the
crankcase.
Do not align the piston pin clip end gap with the
piston cut-out (6).
80
Servicing Your Honda
HONDA O/M CRF450X (Eu) 3RMEY620 00X3R-MEY-6200
(1)
(2)
(3)
(1)
(2)
(4)
(5)
(5)
(6)
(1) piston (4) piston pin
(2) "IN" mark (5) piston pin clips
(3) large valve recesses (6) piston cut-out
Cylinder Installation
1. Clean off any gasket material from the gasket
surface of the crankcase, being careful not to
let any material fall into the crankcase.
Be careful not to remove any metal from the
gasket surface.
2. Remove the shop towel. Do not let any gasket
debris fall into the crankcase.
3. Install the dowel pins (1) and new cylinder
gasket (2).
NOTICE
Do not let the dowel pins fall into the crankcase.
(1)
(2)
(1) dowel pins
(2) cylinder gasket
4. Clean any gasket material off the cylinder.