c) Wheel Change
The tyres are fixed to the wheel rim to prevent them from coming loose. When the tyre is worn down, the entire wheel
has to be replaced therefore.
After loosening of the wheel nut (A), the wheel may be
removed from the wheel axle.
Then the new wheel is plugged on so that the hexagon
socket on the wheel rim's inside is pushed onto the wheel
tappet nut precisely.
Screw the wheel on to the wheel axle with the wheel nut
(A) removed at first. However, do not apply any force for
screwing on. This will require greater force to turn the
wheel, which may damage the drive.
The wheel tappet nut (B) may remain in the rim when re-
moving the rear wheel or detach from the wheel axle (C)
when the wheel is taken off. In this case ensure that the
tappet pin (D) does not fall out and get lost.
When the wheel is later replaced, ensure that the tappet
pin (D) is exactly in the centre of the wheel axle (C) and
inserted into the respective groove of the wheel tappet nut
(B).
If the tappet pin (D) is missing, no torque can be trans-
ferred from the motor to the wheel and the wheel will spin
freely.
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