Arctic Cat 650 Twin2004 Service Manual page 54

2. Rotate the camshaft and note runout; maximum
tolerance must not exceed specifications.
Measuring Camshaft Lobe Height
1. Using a calipers, measure each cam lobe height.
2. The lobe heights must not exceed minimum
specifications.
Inspecting Camshaft Bearing
Journal
1. Inspect the bearing journal for scoring, seizure
marks, or pitting.
2. If excessive scoring, seizure marks, or pitting is
found, the cylinder head assembly must be
replaced.
Measuring Camshaft to
Cylinder Head Clearance
1. Remove the adjuster screws and jam nuts.
CC283D
2. Place a strip of plastigauge in each of the camshaft
lands in the cylinder head.
3. Place the valve cover on the cylinder head and
secure with the valve cover cap screws. Tighten in
correct sequence to specifications.
ATV1013A

NOTE: Tighten cap screws 1-4 with washers to
0.9 kg-m (78 in.-lb), cap screws 5-6 to 1.0 kg-m (87
in.-lb), and cap screws (A) to 1.0 kg-m (87 in.-lb).

NOTE: Do not rotate the camshaft when measur-
ing clearance.
4. Remove the cap screws securing the valve cover to
the cylinder; then remove the valve cover and
camshaft.
5. Match the width of the plastigauge with the chart
found on the plastigauge packaging to determine
camshaft to cylinder head and valve cover
clearance.
CC005D
3
ATV2070
3-25