Honda CRF450L 2019 User Manual

98 Servicing Your Honda
Piston/Piston Rings/Piston Pin
1. Remove the cylinder (1) while holding the
piston (2).
NOTICE
Do not let the cam chain fall into the crankcase.
Do not pry on or strike the cylinder.
2. Remove the dowel pins (3) and cylinder gasket
(4).
NOTICE
Do not let the cam chain fall into the crankcase.
Do not let the dowel pins fall into the crankcase.
1. Place clean shop towels (1) in the crankcase to
keep the piston pin clips, or other parts, from
falling into the crankcase.
2. Remove the piston pin clips (2) using a pair of
needle-nose pliers.
3. Press the piston pin (3) out of the piston (4),
and remove the piston.
Under racing conditions, the piston, rings and
piston pin should be replaced every 8 races or
about every 30.0 hours of running.
NOTICE
Be careful not to damage or shock the piston pin.
Do not clean the piston pin using a commercially
available compound cleaner.
Spread each piston ring (1) and remove by lifting it
up at a point just opposite the gap.
NOTICE
Do not damage the piston ring by spreading the
ends too far.
Cylinder Removal
(1) cylinder (2) piston
(3) dowel pins (4) cylinder gasket
(2)
(1)
(4)
(3)
Piston Removal
(1) shop towels (3) piston pin
(2) piston pin clips (4) piston
(2)
(4) (3)
(1)
(2)
Piston Ring Removal
(1) piston ring
(1)

Honda CRF450L 2019 Specifications

General

Engine Type	449cc liquid-cooled single-cylinder four-stroke
Bore x Stroke	96.0mm x 62.1mm
Compression Ratio	12.0:1
Fuel System	Programmed Fuel Injection (PGM-FI), 46mm throttle body
Transmission	6-speed
Rear Brake	Single 240mm disc
Front Tire	80/100-21
Rear Tire	120/80-18
Rake (Caster Angle)	28.5°
Wheelbase	58.9 inches
Seat Height	37.1 inches
Fuel Capacity	2.0 gallons
Ignition	Full transistorized ignition
Ground Clearance	12.4 inches
Front Suspension	49mm inverted fork; 12.0 inches of travel
Rear Suspension	Pro-Link Showa single shock, adjustable spring preload, compression and rebound damping
Front Brake	Single 260mm disc
Curb Weight	289 pounds
Valve Train	Unicam four-valve
Final Drive	Chain
Trail	4.6 inches (118mm)