Honda 85RB EXPERT 2006, Owner'S Manual

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48
Servicing Your Honda
Piston Removal
1. Place the shop towel in the crankcase.
2. Using a pair of needle-nose pliers, carefully
remove the piston pin clip (1). Avoid letting
it fall into the crankcase.
3. Support the piston (2) and press the piston pin
(3) out of the piston. Remove the piston.
Under racing conditions, the piston and rings
should be replaced after 7.5 hours of running.
Replace the piston pin and connecting rod small
end bearing after 22.5 hours of running.
(1) piston pin clip (3) piston pin
(2) piston (4) piston ring
4. Spread the piston ring (4) and remove by
lifting it up at a point just opposite the gap.
The piston rings may be damaged if their ends
are spread too far.
Cylinder Head/Cylinder Decarbonizing
1. Remove the carbon deposits from the cylinder
head (1) and piston dome.
Take care to avoid scratching the cylinder
head piston dome, or the head gasket surface.
(1) cylinder head
2. Clean carbon deposits from the exhaust port (2)
area.
(2) exhaust port
Cylinder/Piston/Piston Pin/Piston Ring
Inspection
We recommend you consult the Service Manual
or your Honda dealer for correct Service Limit
measurements.
Connecting Rod Inspection
1. Remove the shop towel.
2. Install the bearing and piston pin (1) in the
connecting rod small end and check for
excessive play while holding the connecting
rod. If it feels loose, replace the piston pin
and small end bearing.
(1) piston pin
3. Place the shop towel back in the crankcase.
Cylinder Head Inspection
Check the cylinder head (1) for warpage in
diagonal directions with a straight edge (2) and a
feeler gauge (3).
Service Limit
: 0.004 in (0.10 mm)
(1) cylinder head (3) feeler gauge
(2) straight edge
NOTICE
Cylinder System
(3)
(2)
(4)
(1)
(1)
(1)
(2)
(1)
(2)
(3)
CR85R/047-053 05.6.8 2:21 PM ページ 48