Piston/Piston Pin/Piston Ring Inspection; Piston Ring Installation - Honda CRF450L 2019 Owner's Manual & Off-Road Handbook

Piston/Piston Pin/Piston Ring Inspection

We recommend you consult an official Honda
Service Manual or your dealer for correct Service
Limit measurements.

Piston Ring Installation

1. Remove the carbon deposits from the piston
head and piston ring grooves.
NOTICE
Do not damage the piston when removing the
carbon deposit.
2. Apply engine oil to each piston ring whole
surface.
3. Install the spacer (1) first, then install the side
rails (2) to the piston (3).
4. Install the second ring (4) to the piston with
"RN" mark (5) side facing up.
5. Install the top ring (6) to the piston with "1R"
mark (7) side facing up.
NOTICE
Do not damage the piston ring by spreading the
ends too far.
Do not damage the piston during piston ring
installation.
Piston/Piston Rings/Piston Pin
6. After installing the piston rings they should
rotate freely, without sticking. Space the ring
end gaps 120 degrees apart between top ring,
second ring and spacer. Space each ring end
gap 0.8 in (20 mm) or more apart between
upper side rail, spacer and lower side rail as
shown.
(6)
(5)
(1)
0.8 in (20 mm)
or more
(1) spacer (5) "RN" mark
(2) side rails (6) top ring
(3) piston (7) "1R" mark
(4) second ring
Servicing Your Honda
(6)
(4)
(2)
(1)
(2)
(7)
(4)
(2)
0.8 in (20 mm)
or more
(3)
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