Tracker Off-Road XTR1000 Service Manual page 46

CHECKING CAMSHAFT JOURNAL
DIAMETER
1. Measure the camshaft journal diameter (A):
24.459-24.472 mm (0.9630-0.9635-in.). Replace if
necessary.
SNO-726
2. If the camshaft is within specification, the cylinder
head and camshafts might need to be replaced as a
set.
CHECKING CAM CHAIN/SPROCKET
1. If the cam sprockets have more than 1/4-tooth of
wear (A), the cam sprockets and cam chain should be
replaced. (B) indicates new sprocket thickness.
SNO-767
2. If the camshaft is within specification, the cylinder
head and camshafts might need to be replaced as a
set.
3. If the cam chain or cam sprockets are damaged or
wear is found, the cam chain and cam sprockets
should be replaced as a set.
VALVES
SNO-285
CAUTION
If any valve is discolored or pitted or if the seating sur-
face is worn, the valve must be replaced. Do not attempt
to grind a valve or severe engine damage may occur.
If valves, valve guides, or valve seats require servicing or
replacement, The manufacturer recommends the compo-
nents be taken to a qualified machine shop for servicing.
1. Install the drive clutch; then using a Drive Clutch
Spanner Wrench, rotate the engine two full revolu-
tions.
2. Rotate the engine until the camshaft lobe of the valve
being measured is directly away from the tappet.
3. Using an appropriate thickness gauge, measure and
record the intake and exhaust valve clearance of the
cylinder that is on the compression stroke; then
rotate the engine 360° and measure and record the
valve clearance of the other cylinder. Valve clearance
must be within specifications.
Valve Clearance (Cold)
15°-25° C Intake: 0.15-0.22 mm (0.0059-0.0087 in.)
(59°-77° F)
Exhaust: 0.21-0.25 mm (0.0083-0.0098 in.)
SNO-672
NOTE: At this point if valve/tappet clearances are

within specifications, servicing is complete. If any
valve/tappet clearance is not within specifications,
complete step 15 of the Disassembling sub-section
before proceeding to step 4.
45