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DG and P screws (Plastoform) are used in polymer and lightmetal components. These screws form a
permanent thread when they are installed for the first time. They can be removed and installed as often
as necessary without detrimentally affecting the strength of the screwed assembly, providing the specified
tightening torque is observed. For this reason it is essential to use a torque wrench.
Fastener
Thread
For component
Torque
Remarks
size
Nm
Pan head screw
M5x12
Valve cover
4.0
Pan head screw
M5x22
Valve cover
4.0
Nut
M5
Valve adjusting screw
5.0
Collar nut
M8
Flywheel
15.0
M8
Starter cup
8.0
Nut
M5
Carburetor
5.0
Pan head screw
M6x28
Clutch shoes
10.0
1)
Pan head screw
M8x28
Clutch shoes
15.0
2)
Pan head screw
M4x16
Cam gear cover
3.0
Pan head screw
M5x18
Crankcase
5.0
Pan head screw
M5x55
Crankcase cover
1st stage
3.0
2nd stage
7.0
Spline screw
IS-DG5x24
Gear housing/drive tube
8.5
Spline screw
IS-M5x12
Clamp, control handle/
drive tube (loop handle)
2.0
Spline screw
IS-M5x16
AV sleeve/drive tube (clamp screw)
5.5
Spline screw
IS-M5x12
Clamp, control handle/drive tube
2.0
Spline screw
IS-M5x16
Clamp/drive tube (harness)
4.5
Spline screw
IS-M5x30
Control handle (bike handle)
2.0
Spline screw
IS-M6x25
Clamp/loop handle
4.5
Screw plug
M11x10
Gearhead
8.5
Plastoform screw
IS-P4x16
Control handle/handle moldings
1.0
Collar screw
IS-P3.5x10.6
Detent spring/slide control
(bike handle)
1.1
Nut
M12x1.5 L
Cutting tool
25.0
Spline screw
IS-M5x16
Deflector/gearhead
4.3
All other screws
M3
1.0
and nuts
M5
5.0
M6
9.0
Use the following procedure to fit a DG or P screw in an existing thread:
– Place the DG or P screw in the hole and rotate it counterclockwise until it drops down slightly.
– Tighten the screw clockwise to the specified torque.
This procedure ensures that the screw engages properly in the existing thread and does not form a new thread,
which would weaken the assembly.
1) FS 25-4
2) FS 65-4
Note: Power screwdriver speed settings for polymer:
Plastoform screws
max. 600 rpm
DG screws
max. 500 rpm
6
FS 25-4, 65-4