3.58
9940259 R02 - 2022
RZR
PRO R / PRO R 4 Service Manual
© Copyright Polaris Industries Inc.
PISTON-TO-CYLINDER CLEARANCE
Measure piston outside diameter at a point 13 mm
q
up
from the bottom of the piston, at a right angle to piston
pin bore.
Subtract measurement from maximum measurement
obtained in Step 4 of
“Cylinder Inspection”
procedure.
MEASUREMENT
Piston O.D. (Standard):
3.66 ± 0.0005” (92.970 ± 0.015 mm)
Cylinder to Piston Clearance:
0.0017 - 0.0029 (0.045 - 0.075 mm)
PISTON RING INSTALLED GAP
1. Place each piston ring
q
inside the cylinder
w
. Use
the piston to push the ring squarely into cylinder, as
shown below.
2. Measure installed gap with a feeler gauge
e
at both
the top and bottom of the cylinder.
NOTICE
A difference between top and bottom end gap
measurements is a general indication of cylinder taper
(wear). The cylinder should be measured for taper and
out of round.
1
2
3
0.59 in.
(15mm)
3. If the installed gap measurement exceeds the service
limit, replace the rings.
MEASUREMENT
Piston Ring Installed Gap:
Top Ring:
0.0177 - 0.0236” (0.45 - 0.60 mm)
Service Limit:
0.0275 in (0.7 mm)
Second Ring:
0.0275 0.0374” (0.70 - 0.95 mm)
Service Limit:
0.0401 in (1.02 mm)
Oil Control Rails:
0.0009 - 0.0401” (0.025 - 1.02 mm)
Service Limit:
0.0452 in (1.15 mm)
NOTICE
Always check piston ring installed gap when installing
new rings and/or a new cylinder.
