Frame Noise; Brakes; Generally Poor Or Unpredictable Handling; Loose Steering - Polaris 1999 Sportsman 400 Service Manual

T ROU BLESHO OTI NG
Generally Poor or Unp redictable Handli ng
I. Improper tire inflation pressure .
2. Improperly adj usted whee l alignment.
3. Worn or damaged steering components.
4. Worn or damaged suspensio n compone nts.
5. Bent or broken frame.
Loose Steer ing
1. Loose steering shaft. bushings or steeri ng shaft
fasteners.
2. Loose tie rod ends.
3. Worn spindle bushings.
Une q ual St eer ing
I. Improperly adjusted tic rods.
2. Improperl y adjusted steering stops.
3. Damaged steering components.
4. Uneven front tire pressure.
Steering \Vanders
1. Loose or ,.. ' om steering com ponen ts.
2. Improperly adjus ted wheel alignment (toe a nt).
3. Worn or damaged tires.
4. Damaged shock absorber(s).
5. Bent or broken frame.
FRA.\l E NOISE
Noises traced to the frame or suspens ion arc usu-
ally caused by loose, worn or damaged parts. Vari-
ous noises that arc related to the frame arc listed
below:
I. Disc brake lIoise- A
screec hing sound dur ing
braking is the most common disc brak e no ise. So me
other disc brake associated noises can be caused
by:
a. G
lazed brake pad surface.
b. Excessive ly worn brake pads .
e. Warped brake dise(s).
51
d. Loose brake disc mounting bolts.
e. Loose or missing cal iper mounting bolts.
f.
Damaged caliperts) .
g. Cracked wheel flange or bosses, where the
brake disc mounts to the hub flange .
2. Front shock absorber noise:
a. Crac ked or bro ken shoc k spring(s).
b. Damage shock absorber(s).
c. Loose shock absorber mou nting bolts and
nuts.
3. Rear shock absorber noise:
a. Loose shock absorbe r mounting bolts and
nuts.
b. Cracked or broke n shock spring.
e. Damaged shock absorber(s).
4 . Some other frame associa ted
noises
can be
caused by:
a. Cracked or brokeo frame.
b. Cracke d or broken rear upper and lower sus-
pension
contro l arms.
c. Loose engine mounting bolts.
d. Damaged steering shaft bearings.
e.
Loose mou nting bracket.
BRAKES
The front and rear brake units arc cr itica l to rid ing
performance and safety. Inspect the brake system
frequently and repair any problem immediately.
When replacing or refilling the disc brake fluid, use
only DOT 3 brake fluid from a closed and sealed
container. See Chapter Fourtee n for additional in-
formation un brake fluid selection and disc brake
service. The troubleshooting procedures in Figure
19 will help to isolate the major ity of disc brake
trou bles.
When checking brake pad wear, check that the
brake pads in eac h cal iper contac t the disc squarely.
If one of the brake pads is wearing unevenly. sus-
pect a warped or bent brake disc or damaged caliper,
Ta b le 1 is on the following p a ge.