Positioning At Tdc On The Compression Stroke - Honda CRF450L 2019 Owner's Manual & Off-Road Handbook

Valve Clearance
Positioning At TDC On The
Compression Stroke
1. Remove the right crankcase over cover
(page 83).
2. Remove the crankshaft hole cap (1).
(1)
(1) crankshaft hole cap
3. Remove the spark plug (page 86).
4. Remove the cylinder head cover (page 87).
88
Servicing Your Honda
5. Rotate the crankshaft by turning the primary
drive gear bolt (2) clockwise until "T" mark (3)
on the primary drive gear aligns with the index
mark (4) on the clutch cover. In this position,
the piston may either be on the compression or
exhaust stroke at TDC. If the primary drive
gear passed the "T" mark, rotate the primary
drive gear bolt clockwise again and align the
"T" mark with the index mark.
Make sure that the decompressor weight (5) is
upper position.
crankshaft side: camshaft side:
(4)
(2)
(3)
(2) primary drive gear bolt
(3) "T" mark
(4) index mark
(5) decompressor weight
6. Check the timing marks (6) on the cam
sprocket aligns with the camshaft holder
mating surface (7) of the cylinder head.
(6) timing marks
(5)
(7) camshaft holder mating surface
7. The inspection must be made when the piston
is at the top of the compression stroke when
both the intake and exhaust valves are closed.
This condition can be determined by moving
the rocker arms (8).
(8) rocker arms
(6)
(7)
(8)
(8)