Küschall R33 User manual

Service Manual
KÜSCHALL R33

3
KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
TABLE OF CONTENTS
GENERAL...................................................................................................................... 4
Introduction 4
Spare parts and adaptations 4
Fastening with hexagon socket bolts 4
Torque 5
Checks 5
Identifying and repairing faults 5
SEAT ...............................................................................................................................6
Seat width (SB) 6
Seat depth (ST) 6
Rear seat-to-floor height (SHh) 6
Rear seat height adjustment – Low impact system 6
Rear seat height adjustment – without Low impact system 7
Tipping point adjustment 8
Front seat-to-floor height (SHv) 10
Seat angle (SW) 10
BACKREST...................................................................................................................11
Replacing the backrest tube 12
Backrest angle (RW) 12
Adjusting the backrest height 13
Replacing the handle 14
Replacing foldable push handles 14
FOOTRESTS ................................................................................................................15
Lower leg length (UL) 15
Replacing footrests 15
Adjusting the footrest height 15
Fitting and adjusting high-mounted footrest 16
Angle-adjustable footplate, adjusting the angle 16
SIDE PARTS .................................................................................................................17
Clothes-guard/mudguard 17
Siderests 19
FRONT WHEELS........................................................................................................ 20
Replacing a front wheel 20
Replacing a front wheel fork 20
REAR WHEELS ............................................................................................................21
Control of rear wheel parallelism 21
Adjusting the removable axle 21
Rear wheel axle replacement 22
BRAKES ....................................................................................................................... 23
Parking brakes assembly and adjustment 23
OPTIONS & ACCESSORIES...................................................................................... 24
Antitipper assembly and adjustment 24
Fitting the pelvic belt 24

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
GENERAL
Introduction
This service manual is part of the instructions and contains the tech-
nical information for servicing, configuring and repairing a küschall®
wheelchair.
WARNING!
Danger of accident and severe injuries.
If the wheelchair is improperly set it can cause
accidents and severe injuries.
▸Changes to the wheelchair may only be carried out
by the dealer.
To guarantee the required safety and reliability, all wheelchairs must
be comprehensively checked once a year.
In part, assembly and adjustment require extensive experience. For
this reason, the following assembly instructions have been split into
three categories:
Requirement Symbol
Easy – technical understanding required 
Medium – technical knowledge required 
Dicult – technical knowledge and expertise in
assembling wheelchairs required

The required tools and their respective sizes are listed above each
instruction. The instructions include information on the torques with
which the respective screw connections must be tightened. Adhering
to the given torques requires the use of a torque spanner.
Tool Symbol
Allen key Ã3, 4, 5, 8
Phillips screwdriver Ò2
Open-end spanner 8, 10, 11, 19
Socket spanner/Box spanner 8, 10
Spare parts and adaptations
All spare parts may be obtained from the küschall®Customer Service
department. An electronic spare parts catalogue can be found at
www.kuschall.com. Only original spare parts may be used. The writ-
ten authorisation of Küschall AG must be obtained before installing
additional adaptations on a küschall®wheelchair.
Fastening with hexagon socket bolts
Hexagon socket bolts are not designed to withstand an excessive
application of force. When tightening or undoing a hexagon socket
bolt, force must be applied to the nut wherever possible to avoid
damaging the bolt.
Tightening and undoing
Turn the nut using a socket spanner (only use an open-end
spanner if there is insucient space), using the Allen key simply to
stop the bolt turning.
GL
SB
GB

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
Tightening and undoing when no nut is present
If a hexagon socket bolt is screwed directly into a thread, the bolt must be tightened using
the Allen key
iEnsure that the Allen key is of good quality and not worn.
Torque
All bolts must be tightened with the torque specified in the following instructions.
Checks
Visual check
Check the entire frame for cracks, especially the areas around joints and welded
seams.
Checking the screw connections
Check all bolts with the torques specified in the instructions regularly, and adjust if
required.
CAUTION! Several screw connections have been secured with safety seals. If these are opened,
they must be secured again using new safety seals.
High-power and low power adhesives are available. For torque entries notice shall be
made whether an adhesive and which adhesive needs to be used.
Identifying and repairing faults
Fault Possible cause Action
The wheelchair does not
travel in a straight line
Incorrect tyre pressure on one rear
wheel Correct tyre pressure
One or more spokes broken Replace broken spoke(s)
Spokes tightened unevenly Tighten loose spokes
Front wheel bearings are dirty or
damaged Clean or replace the bearings
The wheelchair tips too
easily
Backrest angle too large Reduce backrest angle
Wrong seat position Change seat position
The brakes are gripping
poorly or asymmetrically
Incorrect tyre pressure in one or
both rear tyres Correct tyre pressure
Brake setting incorrect Correct brake setting
The rolling resistance is
very high
Tyre pressure in rear tyres is too low Correct tyre pressure
Rear wheels are not parallel Make rear wheels parallel
Front wheel axles are restrained by
dirt or hair Clean front wheel axles
Bearings are dirty or faulty Replace the bearings
The front wheels wobble
when moving fast
Too little tension on the clevis pin
housing
Tighten the nut on the castor
fork slightly
Front wheel is worn flat Replace front wheel
The front wheel is sti or
stuck Bearings are dirty or faulty Replace the bearings

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SEAT
SEAT
Seat width (SB)
Available seat widths: SB 340 to SB 440, in 20 mm steps.
Once it has been set the seat width cannot be modified easily. It requires replacing the seat
module, possibly the centerpart, the backrest, axle and possibly the footrest. This modificati-
on is not described in the service manual.
Seat depth (ST)
Available seat depths: ST 375 to ST 475 in 25 mm steps.
Adjusting the seat depth requires replacing the entire seat module including seat upholstery
and rail, as well as the seat cushion.
Rear seat-to-floor height (SHh)
Available rear seat heights: SHh 400 to SHh 490 in 10 mm steps.
To adjust the rear seat height it is necessary to change the rear suspension configuration of
the spring (or fixed connection piece) and distance rings,
Chap. Seat; Rear seat height adjustment with/without „Low-Impact-System“.
The following configurations are possible:
Rear seat height adjustment – Low impact system
4
5
7
1
7
6
2 2
1
3
3
Rear seat-to-floor height by rear wheel
size
with low impact
system
without low
impact
system
SHh 24‘‘
wheel
25‘‘
wheel
24‘‘
wheel
25‘‘
wheel
400 — — S1 —
410 — — S2 S1
420 — — S3 / M1 S2
430 1 — M2 S3 / M1
440 2 1 M3 / L1 M2
450 3 2 L2 M3 / L1
460 4 3 L3 / XL1 L2
470 5 4 XL2 L3 / XL1
480 — 5 XL3 XL2
490 — — — XL3
à7 Nm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SEAT
Diculty:  Tool: Ã5, 8
Loosen the bolts and remove bolt .
Lift up the seat module and remove the spring , elastomer and distance
rings (if fitted).
Insert spring , elastomer and distance rings according to the required rear
seat height, Table Rear seat-to-floor height by rear wheel size (SHh).
Turn the clamp on the seat module against the spring unit, until all parts fit
together.
Fasten the spring unit with the bolt (with adhesive). Make certain to use the
correct bolt length, Table Rear seat-to-floor height by rear wheel size (SHh).
Tighten the bolts .
Rear seat height adjustment – without Low impact
system
Diculty:  Tool: Ã5, 8
Loosen the bolts and remove bolt and rings (if fitted).
Lift up the seat module and remove the seat-to-frame connection and the
distance rings (if fitted).
Insert seat-to-frame connection , with or without the distance rings ,
according to the requested rear seat height, Table Rear seat-to-floor height by
rear wheel size (SHh).
Turn the clamp on the seat module against the seat-to-frame connection,
until all parts fit together. Fasten the seat-to-frame connection with the
bolt (with adhesive). Slide 1 or 2 rings onto the bolt if necessary,
Table Rear seat-to-floor height by rear wheel size (SHh).
Tighten the bolts .
2
3
7
7
1
6
5
2
3
1
4
4
à7 Nm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SEAT
Tipping point adjustment
The tipping point of the wheelchair can be adjusted by changing the
horizontal position of the seat module.
Making it easier to tip the wheelchair
Diculty:  Tool: Ã4, 5
Loosen bolts .
Remove bolts (=4 bolts that connect the rear brace and the seat
module ).
Move the rear brace forward and use the bolts to secure it in the
required position.
Remove bolts (=4 bolts that connect the front brace and the
seat module ).
Move the front brace forward and use the bolts to secure it in
the required position.
Retighten the bolts .
Making it more dicult to tip the wheelchair
Diculty:  Tool: Ã4, 5
Loosen bolts .
Remove bolts (=4 bolts that connect the front brace and the
seat module ).
Move the front brace backwards and use the bolts to secure it in
the required position.
Remove bolts (=4 bolts that connect the rear brace and the seat
module ).
Move the rear brace backwards and use the bolts to secure it in
the required position.
Retighten the bolts .
iAdditional positions can be set by turning the front brace . In this
case, the fastening elements must be moved.
When tightening the fastening elements , it must be ensured that the slots in the fastening elements are parallel to one another and
that the distance of both fastening elements from the centre part is
identical.
1
2
3
4
5
6
7
à7 Nm
à7 Nm
à7 Nm
à13 Nm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SEAT
1
1
2
2
3
3
4
4
5
Seat position and tipping point
Seat position
(1=rearmost,
6=frontmost
seat position)
Dimension x
(the larger
the value of
x, the easier
it is to tip the
wheelchair)
Front brace
(1=frontmost,
4=rearmost
position of brace
at seat module)
Rear brace
(1=frontmost,
5=rearmost
position of brace at
seat module)
Bracket distance
(=distance
between brackets
of front brace)
Brace distance
(=distance
between rear
brace and front
brace)
1 154 1 1 small 190
2 131 2 2 small 190
3 108 3 3 small 190
4 85 4 4 small 190
3 108 1 3 large 236
4 85 2 4 large 236
5 62 3 5 large 236
6 39 4 5 large 213

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SEAT
Front seat-to-floor height (SHv)
The front seat height is variable between SHv 460 and SHv 510
(± 10 mm).
The front seat height is dependent on several factors that interact with
each other. In addition to the size of the rear wheels, the frame, seat
depth and rear seat height influence the seat height.
The following combinations of front and rear wheels are possible:
Front and rear wheel combination
Rear
wheel Frame
Front wheel
3'' 4'' 5''
24’’ 75° D C B
90° B A —
25’’ 75° E D C
90° C B —
iOnly choose wheel and axle combinations specified in the table to ensure that the frame is straight and the axis of the front wheel fork is
perpendicular to the ground.
To achieve the desired front seat height, there are three frames of
dierent heights available (long, medium, short):
Seat angle (SW)
The seat angle is determined by the dierence between the rear seat
height (SHh) and the front seat height (SHv).
25
24
3'' 4'' 5''
A B C D E F
75°
90°
Frame SHv
24’’ 25’’
long 500 510
medium 480 490
short 460 470

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
BACKREST
BACKREST
The adjustable back is fitted with velcro bands and a cover. Apart
from the adjustable back there is the light cover, which is produced
individually for each backrest height (RH) and seat width (SB).
A 1-band strap is placed beneath the stabilizing bar if there is a
clothes-guard, and a 2-bands strap if there is a mudguard.
Backrest height (RH) to pushhandles,
telescopic tubes and bands
RH
without pushhandles 
bands above
stabilizing bar
top
band
telescopic
tube bended

270 1-band 
endband, 10 cm 
S
285 1-band S
300 1-band S
315 1-band S
330 2-bands S
345 2-bands S
360 2-bands S
375 2-bands+1-band M
390 2-bands+1-band M
405 2-bands+1-band M
420 2-bands+1-band M
435 4-bands L
450 4-bands L
465 4-bands L
Backrest height (RH) to cover, backrest tube, pushhandles and bands
RH cover backrest
tube
standard pushhandles 
foldable pushhandles 
pushhandle 
telescopic tube
straight 
bands above
stabilizing bar
top
band
270 S S S 1-band 
10 cm backrestband, 2 parts 
285 S S S 1-band 
300 S S S 1-band 
315 S L S 1-band 
330 S L S 2-bands 
345 M L S 2-bands 
360 M L S 2-bands 
375 M L S 2-bands+1-band
390 M L L 2-bands+1-band
405 M L L 2-bands+1-band
420 L L L 2-bands+1-band
435 L L L 4-bands 
450 L L L 4-bands 
465 L L L 4-bands 
5
6
9
1
2
3
10
8
8
7
7

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
BACKREST
Replacing the backrest tube
Diculty:  Tools: Ã3,4 8, 10
Remove the backrest padding.
Slide the backrest bands upwards or downwards to gain access to
the screws . Remove the screws and nuts on both sides.
Remove the push handles or the telescopic tubes and remove the
upper Velcro®bands.
Remove the screws on the backrest joint.
Remove the lower Velcro®bands and the sleeve with the
adjustment screwfrom the backrest tube and fit both to the
new backrest tube.
Fit the backrest tube to the backrest joint with the screws . Here,
first fit the lower screw followed by the upper screw.
Fit the upper Velcro®bands and the push handles or the
telescopic tubes again and fix them with screws and nuts.
Carry out the same setting on both sides.
Refit the backrest padding.
The excentre plates must be adjusted identically on both sides of
the wheelchair, Adjusting the backrest angle.
Check:
Check the settings of the adjustment screws on both sides. The
screw head must only lightly touch the seat module when the
backrest is in the upright position. If necessary, readjust the length by
releasing the counter nut and tightening or loosening the adjustment
screw. Then retighten the counter nut .
Incorrectly adjusted adjustment screws result in damage to the
backrest joint’s mechanism, Adjusting the backrest joint.
Backrest angle (RW)
The angle of the backrest can be changed by repositioning the ex-
centre plate in the backrest joint plate.
The following angles (measured from the seat) can be set:
1
2
4
3
à7 Nm
à7 Nm
à7 Nm
5
6
86°
90°
78°
82°
82°
74°
74° 78° 82° 86° 90°
86°
90°
78°
82°
82°
74°
86°
90°
78°
82°
82°
74°
86°
90°
78°
82°
82°
74°
86°
90°
78°
82°
82°
74°

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
BACKREST
Adjusting the backrest angle
Diculty:  Tools: Ã3, 10
Fold down the backrest and release the counter nut of the
adjustment screw and screw it in completely.
Remove the screw on the excentre plate . Remove the
excentre plate and reinsert it in the desired position.

The excentre plates must be set identically on both sides of the
wheelchair.
Reinsert the screw and tighten it.
Fold the backrest up until the stop bolts engage and unscrew
the adjustment screw until it touches the frame and the
backrest joint no longer moves.
Tighten the counter nut .
Adjusting the backrest joint
Diculty:  Tools: 10
Put the backrest up and let the pin engage.
Press the backrest forwards to ensure the joint cannot move.
Unscrew the screw until it touches the spigot of the seat
frame.
Screw the screw back in by between a ¼ and a ½ turn and
counter with the counter nut .
Correctly adjust the backrest joint on both sides.
Function check:
Sit in the wheelchair and lean back so that the backrest is strained.
Upon pulling the release cord , the pin must be easily removed
on both sides and must fully glide back in upon letting go of the
release cord.
Adjusting the backrest height
Readjusting the push handle/telescopic tube
Diculty:  Tools: Ã3 8
Remove the backrest padding.
Remove the screw connection and adjust the desired height
of the push handle or the telescopic tube. Insert the screw
connection again and tighten the nut.
Carry out the same setting on both sides.
Refit the backrest padding.
iIf the desired height cannot be achieved, you must use a dierent
telescopic tube or push handle.
1
4
2
3
1
5
4à4 Nm
à7 Nm
4
3
3
5
2
1à7 Nm
1
à7 Nm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
BACKREST
Replacing the handle
An adhesive (e.g. hair spray) is used in these instructions. When
applied to the handle, this substance works as a lubricant and as an
adhesive once dry.
After drying, the adhesive used must be able to resist a pull-o force of 750 N. If in doubt, contact Küschall AG.
Diculty: 
Remove the old handle.
Remove any residue (residual adhesive, grease, dust) from the
push handle tube.
Apply a thin layer of hair spray all over the surface of the push
handle tube onto which the handle is to be slid.
Apply a thin layer of hair spray to the inside of the handle.
Slide the new handle onto the push handle tube.
Move the handle into the correct position (grooves facing
upwards).
i
If a long handle has been fitted and this is to be replaced with a
short one, the push handle tube must be shortened by 35 mm.
The push handle tube must be replaced when switching from a
short to a long handle.
Replacing foldable push handles
Diculty:  Tools: Hole punch pliers 6 mm, Ã3, 4
Remove the old foldable push handle.
Pull down the backrest cover G on the telescopic tube, until its
hole B is uncovered.
!IMPORTANT! Make sure that the threaded insert F(part no. 1580450) supplied
with the new push handle is used for assembly.
Place the threaded insert Fin the telescopic tube.
Punch a hole through the backrest cover with a distance of
10 mm from the upper egde, using hole punch pliers (see graphic
below).
Slide the new foldable push handle Aonto the telescopic tube.
Fix the foldable push handle with screw C(M5x12).
Pull up the backrest cover, until it covers completely the rear hole
in the pushhandle.
Fix the foldable push handle with screw D(M5x14) and washer H.
Check screws Eon both sides of the push handle and re-tighten
if necessary.
Carry out the same steps for the other push handle.
!IMPORTANT! Make sure that the folding force is approximately 5 N (0.5 kg).
i
The retrofit of foldable push handles requires new tubing.
Cà3 Nm (low-strength)
Dà7 Nm (low-strength)
10 mm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
FOOTRESTS
FOOTRESTS
The footrest must be selected in accordance with the seat width.
A standard footrest and an angle-adjustable footrest are available.
Furthermore, there is the possibility of a high-mounted footrest.
Lower leg length (UL)
To change the lower leg length, the footrest can be fixed at a high-
er or lower position. Table, Chap. Frame. The shortest lower leg
lengths can be achieved using the high-mounted footrest.
Fitting and adjusting high-mounted footrest
Replacing footrests
Diculty:  Tools: Ã48
Remove the screw connections on both sides.
Remove the footrest and replace it with a new one.
Tighten the screw connections on both sides.
Carry out the same setting on both sides.
Adjusting the footrest height
Diculty:  Tools: Ã48
The height of the footrest can be adjusted in 10 mm steps.
Remove the screw connections on both sides.
Slide the footplate to the desired height.
Tighten the screw connections on both sides.
Carry out the same setting on both sides.
iIf the desired lower leg length cannot be achieved, a high-
mounted footrest must be used Fitting and adjusting a high-
mounted footrest
1
à4 Nm
1
à4 Nm

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
FOOTRESTS
Fitting and adjusting high-mounted footrest
Diculty:  Tools: Ã4, 5 8, 10
Fit the frame bar for the high-mounted footrest to the front
frame on both sides using the screw connections .
Fix the clamp set to both sides of the frame using the screw
connection . Only tighten lightly.
Slide the high-mounted footplate into the clamp set and to the
desired height.
Tighten the screw connections on both sides.
Angle-adjustable footplate, adjusting the
angle
Diculty:  Tools: Ã410
To adjust the angle, release the four screw connections until the
footplate can be moved.
Check and/or adjust the distance between the left and the right
sides by pushing in or pulling out the tubes below the footplate
in such a way that the bearings blocks are perpendicular to the
ground.
Tilt the footplate into the desired position and tighten the screw
connections .
The angle of the footplate must be set so that the user’s feet cannot slide o the plate.
1
4
5
2
3
à7Nm
à7 Nm
1
1
à13 Nm

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KÜSCHALL R33
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Service Manual
SIDES
SIDE PARTS
Clothes-guard/mudguard
The clothes-guard fitted as standard can be replaced by a mudguard.
Clothes-guard and mudguard are available in plastic or in carbon. For
the carbon mudguard there is an additional size (XL) for the two
smallest rear seat hights (SHh).
Mudguard size carbon
Wheel size
SHh 24‘‘ 25‘‘
400 L L / XL
410 L L
420 L L
430 L L
440 M L
450 M L
460 M L
470 M M
480 M M
490 M M
L
XL
Mudguard size plastic
Wheel size
SHh 24‘‘ 25‘‘
400 L L
410 M L
420 M L
430 M L
440 M M
450 M M
460 M M
470 M M
480 M M
490 M M
L
Clothes-guard size
Wheel size
SHh 24‘‘ 25‘‘
400 L L
410 L L
420 L L
430 L L
440 M L
450 M L
460 M L
470 M M
480 M M
490 M M
L
M

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KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SIDES
Replacing the clothes-guard
The mounting element on the backrest must already be fitted.
Diculty:  Tools: Ã3, 4
If present, remove the clothes-guard to be replaced by loosening
the screw connection .
Check the correct position of the clothes-guard with fitted rear
wheel. Here, find the suitable height on the clothes-guard for
fixing the screw connection to the backrest mount .
If necessary, the holder on the seat module can be replaced.
Here, remove the screw .
i
The clothes-guard is correctly positioned if it can be inserted
between the seat module and the holder and the upper edge runs
above the rear wheel.
Fitting the mudguard
Diculty:  Tools: Ã3, 410 Ò2
Remove the clothes-guard and the mounting elements on the back-
rest and the seat.
Fit the holder to the seat module using the screw connections 
and then refit the rear wheel.
Slightly loosen the screws on the adjustment plate and slide
it along the mudguard carrier until the mudguard is at the right
height.
The position of the mudguard can also be adjusted: Here, loosen
the screw connections and , position the mudguard as
required and tighten the screw connections and again.
Tighten the screws again.
Carry out the same setting on both sides.
By tightening or loosening the screws you can adjust how easily
the armrest can be pulled out or pushed in.
iThe existing axle may not be suciently long for the new configuration with mudguard. In this case, a longer axle must be
fitted. Changing the wheel chamber / fitting and adjusting an
axle
The distance between the mudguard and the wheel must be > 25 mm in loaded condition to prevent fingers from becoming
caught between the wheel and the mudguard.
1
3
4
2
5
6
à4 Nm
à7 Nm
à4 Nm
2
3
4
1
5
à7 Nm
à4 Nm
à7 Nm
à7 Nm

19
KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
SIDES
Siderests
Fitting and adjusting a height-adjustable siderest
Diculty:  Tools: Ã4, 5 Ò2
Fit the holder and the bracket to the seat module on both
sides. Tighten the screws only lightly.
Fit the bar between the two brackets using the screws .
Tighten the screws .
To adjust the armrest height, insert the armrest into the
holder .
Loosen the screws for the height adjustment and slide it into
the desired position.
Then retighten the screws for the height adjustment.
By tightening or loosening the screws , you can adjust how
easily the armrest can be pulled out or pushed in.
6
1
1
2
3
4
7
5
2
8
à7 Nm
à7 Nm
à4 Nm

20
KÜSCHALL R33
© Küschall AG, Switzerland | 2014-07
Service Manual
FRONT WHEELS
FRONT WHEELS
Replacing a front wheel
Diculty:  Tools: Ã2x3
Remove the screw with disk on one side. Remove the wheel
axle .
Remove the front wheel .
Place the sleeves between the new front wheel and the fork.
Slide the axle through the fork, sleeves and the front
wheel and fix the axle using the screw . Here, use the new
screw supplied with the wheel as this screw comes with a thread-
locking device.
Function check:
The wheel may not wobble, but must rotate easily.
Replacing a front wheel fork
Diculty:  Tools: 10
Remove the sealing cap of the bearings block by inserting two
screwdrivers into the grooves and flipping it o.
Remove the nut with the washer .
Remove the front wheel fork .
Check the ball bearings and replace them if necessary.
Insert the new front wheel fork with the washer and the nut 
and tighten the nut.
Carry out the function check (see below).
Replace the sealing cap .
Function check:
Tip the wheelchair backwards by 90° so that it is lying on the backrest
and the rear wheels. Turn the fork upwards (position A) and let it tip
downwards.
The fork has been correctly adjusted if it easily turns to beyond the
bottommost point and remains there (position B).
If the fork turns back to the lower position (position C), it has not
been suciently tightened. There is a risk that the front wheels will
start to wobble at high speeds.
2
3
1
4
4
1
1
2
3
4
5
4
A
B
C
à4 Nm