Snowmobile Polaris PRO X (2003 year). Instruction - part 55

STEERING / FRONT SUSPENSION

6.8

Springs

Two types of springs are employed in Polaris suspen-
sions, coil springs and torsion springs. Following is some
of the terminology used when referring to coil springs.

Free length - the length of a coil spring with no load ap-
plied to the spring.

Installed length - the length of the spring between the
spring retainers. If the installed length of the spring is
less than the free length, it will be pre-loaded.

NOTE: All springs must have pre--load or damage to the
retainers and shock may occur.

Spring rate - the amount of force required to compress a coil spring one inch. For example, if 100 pounds
of force is required to compress a spring 1 inch, the spring rate would be 100 #/in.

Straight rate spring - the spring requires the same amount of force to compress the last one inch of travel
as the first one inch of travel. For example, if a 100 #/in. spring requires 100 pounds of force to compress
it one inch, 300 pounds of force would compress it three inches, 400 pounds of force would compress it three
inches, and so on. Thus if you had a 5 inch 100#/in spring, the amount of force to fully compress this spring
would be 500 lbs of force.

Progressively wound spring - the rate of the spring increases as it is compressed. For example, a 100/200
#/in. rate spring requires 100 pounds of force to compress the first one inch, but requires 200 additional
pounds to compress the last one inch. For example if you had a 9 inch 100/200 #/in spring the required force
to fully compress this spring would be 1000 lbs of force

Dual Rate Springs - When a bump is encountered by the suspension, the force of the bump compresses
the spring. If the force were 450 pounds, a 100 #/in. spring would compress 4.5 inches. A 150 #/in. spring
would only compress 3 inches. If the suspension had 4 inches of spring travel the 100 #/in. spring would
bottom out, while the 150 #/in. spring would have one inch of travel remaining.

Coil
Spring
Length

Installed
Length with
no load to
the spring

STEERING / FRONT SUSPENSION

6.9

Dual Rate Springs

During initial compression of dual rate springs (two
separate springs stacked on top of each other, both
springs will compress resulting in an initial spring rate
that is a combination of both springs, yet less than ei-
ther of the individual springs. The chart at right shows
the initial combined spring rate using two individual
spring rates. The initial spring rate is based on the for-
mula below. For example, if you stack a 150 lb/in.
spring in combination with a 225 lb/in. spring, the chart
will give you an initial spring rate of 90 lb/in.

As the springs compress, there is a point where the
small spring compresses to solid, or the spring retain-
er contacts the transition spacers. This point is called
the transition point. Any compression of the springs
after this point is reached will result in a spring rate
equal to the spring rate of the long spring. This is true
because the smaller spring is no longer being com-
pressed.

Initial Rate=(Spring Rate #1) x (Spring Rate #2)

(Spring Rate #1) + (Spring Rate #2)

Example:

(150 lb/in) x (225 lb/in)=
(150 lb/in) + (225 lb/in)

33750=90 lb/in. initial spring rate
375

STEERING / FRONT SUSPENSION

6.10

Torque Application List

Due to the special grade bolts and nuts required for specific applications, observe the following torque values in
the areas specified. Refer to exploded views for torque values and orientation of components and fasteners.

440 Pro X Fan, 440 / 600 / 700 / 800 EDGE Pro X

Illustration depicts proper orientation of rod ends and bolts on steering components.

Torque Specifications

16--20 ft lbs(22--28Nm)

28-30 ft.lbs (38-41 Nm)

35-40 ft.lbs (47-54 Nm)

55-65 ft.lbs (61-90Nm)

90--100 ft.lbs (124--138 Nm)

Apply Premium All Season Grease, PN2871322 (3oz.), to all grease zerks located on suspension
assemblies.

Replace locking fasteners if removed.

E (Lower Rod)

D (Upper Rod)

E (Lower Rod)

STEERING / FRONT SUSPENSION

6.11

Inspection

Prior to performing steering alignment, inspect all steering and suspension components for wear or damage and
replace parts as necessary. Refer to steering assembly exploded views in this chapter for identification of
components and torque values of fasteners. While disassembling, make notes of what direction a bolt goes
through a part, what type of nut is used in an application, in which direction do the steering arms go on - weld up or
weld down, etc.

Some of the fasteners used in the IFS are special and cannot be purchased at a hardware store. Always use
genuine Polaris parts and hardware when replacing front end components.

Review steering adjustment

guidelines on page 6.14 before making adjustments.

The following components must be inspected before each event.

NOTE: Always follow rod end engagement guidelines found later in this chapter. Maximum setup width must
be checked whenever front suspension components are adjusted or replaced.

- Tie rods and tie rod ends

- Radius rods and radius rod ends

- Torsion bar and bushings / linkage (where applicable)

- Handlebars and steering post assembly

- Spindles and bushings

- Trailing arms and bushings

- Skis and skags

- Bell crank / Pitman arm / Idler arm

- Steering arms

- Shock absorbers, shock mounts, springs

- All related fasteners - check torque. Refer to steering exploded views at the beginning of this section.

- Grease all fittings.

Alignment Bar Specifications

Common Alignment Bar

s (114.3 cm)

=.623-.625s (5/8)
(15.83-15.88 mm)

Material:

C-1018 Steel

Diameter:

.623

s - .625s (5/8s)

(15.82 - 15.87 mm)

Length:

s (114.3 cm)

Content .. 53 54 55 56 ..