Bosch BULLS 650-185, Operating Instructions Manual

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83
Operation
6.5.5 Handlebars

Check handlebar width and hand position.
 Choose different handlebars if necessary.
Contact specialist dealer.
6.5.5.1 Handlebar width
The handlebar width should be as wide as the
rider's shoulders as a minimum. This is measured
from mid-point to mid-point on the hand contact
surfaces.
Figure 78: Determining the optimal handlebar width
The wider the handlebars are, the more control
they provide, although wide handlebars require
greater supporting force. Wider handlebars are
particularly useful to ensure a safer ride for loaded
touring bikes.
6.5.5.2 Hand position
The hand is an optimal position on the handlebars
when the forearm and hand are in a straight line,
i.e. the wrist is not bent. In this way, the nerves are
not pinched and do not cause pain.
Figure 79: Distribution of nerves with curved and straight
handlebars
The narrower the shoulders are, the greater the
bend of the handlebars should be (maximum 28°).
Straight handlebars are advisable for sports bikes
(e.g. MTB). They support direct steering
behaviour, but lead to peaks in pressure and
greater muscular strain on the arm and shoulder
muscles.
6.5.5.3 Adjusting the handlebars
The handlebars and their position determine the
posture that the rider adopts on the
ebike
.
1 After selecting the seating position (see
Section 6.6.2.1), determine the angle of the
upper body and of the upper arm.
2 Pre-tension the back muscles when adjusting
the handlebars. The only way to stabilise the
spine and protect it from excessive strain is
with the back and abdominal muscles pre-
tensioned. Passive muscles are not able to
perform this important task.
3 Set the required handlebar position by
adjusting the stem height and angle (see
Section 6.6.6).
4 After adjusting the handlebars, check the
saddle height and seat position again. The
position of the
hips
on the saddle may have
changed when the handlebars were adjusted.
This can have considerable impact on the
position of the hip joint due to the
hips
tilting
and may change the usable leg length on the
saddle support by up to
2 inches
.
5 Correct the saddle height and sitting posture if
necessary.
28°
_
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