11-5
ZRA_Aero Z Owner’s Manual
OM_ZRA_Aero Z_0913RevA
CHAPTER 11: CASTERS And FORKS
Replacing Casters
Tools Needed:
• Two #2 Phillips Head Screwdrivers
1. Remove the screws, washer, C spring washer, and axle that secure the caster to the fork. Use one screwdriver to
hold one screw in place and a second screwdriver to loosen the other screw. See Figure 11-8.
2. Remove the caster and spacers from the fork.
3. Install the new caster, spacers, washer and C spring washer onto the fork and securely tighten the two screws so
there is no space between the caster, the spacers and the fork sides. Use one screwdriver to hold one screw in
place and securely tighten the other screw with the second screwdriver.
Note: If your chair has 4” or 5” TiLite performance casters, make sure that Spacer 2 (which is wider than Spacer 1) is
positioned on the recessed side of the caster, which should be oriented outwards when the casters are in the trailing
position.
Relacing the Elastomer Shock
Tools Needed:
• Two 5/32” Allen Wrench
1. Remove the Allen screws from the hinge and push out
the threaded spacer. See Figure 11-7.
2. Separate the two halves of the Frog Legs
®
to release
the elastomer shock.
Note: The metal disc is glued to the top of the elastomer
shock.
3. Install the new elastomer shock (making sure the metal
disk is facing upward).
4. Push rmly on the two halves of the Frog Legs
®
to
facilitate reinstalling the Allen screws and threaded spacer.
IWARNING
The threads on the Allen screw that connects the two halves of the Frog Legs
®
are treated with Loctite
®
242
®
, a
medium strength thread lock. If you loosen this Allen screw, you MUST remove and reapply Loctite
®
242
®
or an
equivalent medium strength thread lock.
If you ignore this Warning, your rear wheel could become loose or fall off
and you could fall, tip over or lose control of the wheelchair and seriously injure yourself or others or damage the
wheelchair.
Replacing Frog Legs
®
Tools Needed:
• 5/32” Allen Wrench
• 3/16” Allen Wrench
1. Remove the casters. See “Replacing Casters” on page 11-5.
2. Using the 5/32” Allen wrench, remove Allen Screw 1 (outer screw) and the washer. See Figure 11-8.
3. Using the 3/16” Allen wrench, remove Allen Screw 2 (center screw) and the washer. Holding the caster end
cap and caster mount in place, slide the old Frog Legs
®
fork and caster cap out and slide the replacement Frog
Legs
®
fork through the caster housing and into the caster mount.
4. Using a Bubble Level Bracket, you must square the barrel of the Frog Legs
®
to the level surface because
the at edge of the Frog Legs
®
fork is not parallel to the caster mount assembly. See Figure 11-13
5. Using the 3/16” Allen wrench, place Allen Screw 2 through the washer, end cap and into the caster mount.
Do not tighten. While holding the fork in place, and with the end cap tabs engaged in the tab slots, check to see
if one of the six perimeter holes in the caster end cap aligns with one of the three threaded holes in the caster
mount. If so, proceed to Step 7. If not, proceed to Step 6.
6. Pull the caster end cap away from the caster housing and rotate the caster end cap one-sixth turn and re-engage
the caster end cap tabs in the tab slots. Again, check to see if one of the six perimeter holes in the caster end cap
aligns with one of the three threaded holes in the caster mount. If so, proceed to Step 7. If not, repeat this Step 6
using the next combination of caster end cap tabs and tab slots.
Figure 11-7
Replacing the Elastomer Shock on Frog Legs
®
Allen Screw and
Threaded Spacer
Elastomer
Shock
Fork Stem
Metal Disk
Hinge