Bosch BULLS Twenty 6 EVO, Translation Of The Original Operating Instructions, Page: 59 / 116

MY20B01 - 52_1.0_02.10.2019
59
Operation
6.5.9 Setting the FOX rear frame damper
Only applies to pedelecs with this equipment
6.5.9.1 Adjusting the negative deflection

Negative deflection depends on the rider's
weight and sitting position. The recommended
value is between 25% (hard) and 30% (soft) of
the
total rear frame damper deflection .
1 Turn the pressure level adjuster to the OPEN
position.
2 Attach a high-pressure damper pump to the air
valve.
3 Adjust the rear frame damper air pressure to
the rider's weight.
4 Slowly compress the damper to over 25 % of
the deflection 10 times until you have reached
the desired pressure.
 This equalises the air pressure between the
positive and negative air chambers. The high-
pressure damper pump pressure gauge
changes.
5 Remove the high-pressure damper pump.
Figure 64: FOX rear frame damper
6 Measure the distance between the air chamber
seal (1) and the end of rear frame damper (3).
This gap is the
total deflection for the rear
frame damper (5).
7 Sit on the pedelec in your usual riding position
and support yourself against an object, such as
a wall or tree.
8 Push the O-ring (4) downwards against the air
chamber seal (1).
9 Get off the pedelec without the suspension fork
deflecting.
 Measure the distance between the air chamber
seal (1) and the O-ring (4). This measurement
is the
negative deflection (2). The
recommended value is between 25% (hard)
and 30% (soft) of the
total deflection for the
rear frame damper (5).
10 Increase or reduce the air pressure until you
have reached the desired negative deflection.
6.5.9.2 Adjusting the rebound
The rebound adjuster defines the speed at which
the rear frame damper rebounds after being
subjected to load or impact. The rebound setting
depends on the air pressure setting. A higher
negative deflection requires a lower rebound
setting.
1 Attach a high-pressure damper pump to the air
valve.
2 Read the air pressure.
3 Remove the high-pressure damper pump.
Figure 65: FOX rebound adjuster wheel (1) on the rear
frame damper
Notice
If the air pressure in the rear frame damper is
exceeded or undershot, the damper can be
permanently damaged.
Do not exceed the maximum air pressure of
350 psi (24.1 bar). The minimum air suspension
pressure of 50 psi (3.4 bar) must be complied
with.
25-30%
2
1
3
4
5
1