Bulls 21-17-1093, Translation Of The Original Operating Instructions

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MY21B01 - 22_1.0_02.09.2020
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Overview
3.1 Description
3.1.1 Wheel
Figure 3: Visible wheel components
1 Tyres
2 Rim
3 Spoke
4 Spoke nipples
5 Hub
6 Valve
The wheel comprises the wheel itself, an inner
tube with a valve and a tyre.
3.1.1.1 Valve
Each wheel has a valve. It is used to fill the tyre
with air. There is a valve cap on each valve. The
screw-on valve cap keeps out dust and dirt.
The pedelec either has a conventional Dunlop
valve, a Presta valve or a Schrader valve.
3.1.2 Suspension
Both forks and suspension forks are fitted in this
model series.
3.1.2.1 Rigid fork
Rigid forks do not feature suspension. They transfer
the used muscle and motor power to the road to
optimum effect. Pedelecs with rigid forks consume
less energy on steep roads and have a greater range
than pedelecs with adjusted suspension.
3.1.2.2 Suspension fork
A suspension fork is based either on a steel spring or
air suspension.
Unlike a rigid fork, a suspension fork has two
functions which improve floor contact and comfort:
suspension and damping. The suspension prevents
an impact, such as one caused by a stone lying in the
pedelec's path, from being channelled directly into
the rider's body via the fork. The impact is absorbed
by the suspension system instead. This causes the
suspension fork to compress.
Figure 4: Without suspension (1) and with suspension (2)
After compressing, the suspension fork returns to
its original position. If there is a damper, it
decelerates movement, preventing the
suspension system from springing back in an
uncontrolled manner and stopping the fork from
vibrating up and down. Dampers which dampen
compressive deflection movements, i.e. a
compression load, are called compression
dampers or compression dashpots.
Dampers which dampen rebound deflection
movements, i.e. a rebound load, are called
rebound dampers or dashpots.
The compression can be disabled in any suspension
fork. A suspension fork will then behave like a rigid
fork.
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