80
Servicing Your Honda
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).
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.
(1)
(3)
(2)
(5)
(4)
(2)
(1)
(6)
(5)
(1) piston
(4) piston pin
(2) “IN” mark
(5) piston pin clips
(3) large valve recesses
(6) piston cut-out
17 CRF450X̲31MEY710.indb 80
17 CRF450X̲31MEY710.indb 80
2016/06/08 11:45:59
2016/06/08 11:45:59