Adjusting to load
The luggage carriers of the GrassHopper are
mounted to the suspended part of the frame.
That way your luggage is also fully suspended
and it spares the material. Most notably, even
under heavy load the suspension will
compensate an uneven road much better and
quicker compared to a design where the
luggage carrier would be mounted to the
unsuspended parts, e.g. the rear swing arm.
Additional luggage changes the load of the
wheels and their suspension.The suspensions
are more compressed through the load.That
way, there is less suspension travel for bumps
while riding.Your suspension could seize up
more often.
The suspension of the front wheel is less
affected since luggage at the rear rack almost
only puts weight on the rear wheel. Only in
case of heavy luggage on the lowrider under
the seat is there an influence on the front
wheel.
In order to compensate the variations in the
load you can change the pre-load. For details
see the following chapter.
Theoretically this can compensate for a load
change of approx. 10 kg (23 lbs) at the rear
wheel. In case of higher variations in the load
you would have to exchange the spring for
another spring with another spring stiffness. In
practice you can often do without it: the
GrassHopper offers with 90 mm (3
1
/
2
") a lot
of suspension travel for a touring bike.When
you choose the spring stiffness so that the full
90 mm are at your disposal when your
recumbent is under maximum load, you will
have a somewhat smaller but still very
comfortable suspension travel when you ride
without luggage.
The optional air shock DT-S
WISS
XM180 can
be easily pumped up to compensate load
increases.
Adjusting y
our ne
w bik
e
17
HP
Velotechnik
You should always set the damping as low as
possible to give the bicycle the possibility to
quickly react even to several bumps in a row.
You can ride the GrassHopper with a consid-
erably lower damping than for example a MTB:
due to the relaxed and steady position of the
body the recumbent does not experience ex-
treme variations in the load as it is known
from dancing on the pedals while riding uphill
on a mountain bike.
In addition to this, varying pedaling forces have
very little influence on the suspension of the
bicycle due to the No Squat design of the sus-
pension system of the GrassHopper. So when
you adjust the damping, always start with a low
damping.
It is necessary to choose the correct spring
stiffness to have a well operating suspension
system.The spring stiffness is a measure for
the compression of a spring at a certain load.
It is either given in "N/mm" (Newton per
Millimeters) or "lbs./inch" (Pounds per Inch).
Sometimes you only find "lbs." printed on the
springs.
The spring stiffness of the optional air shock
DT-S
WISS
XM180 is set by adjusting the air
pressure.
The suspension is designed in a way that the
spring compresses considerably when you
mount your bicycle.This is called negative sus-
pension travel (or "sag") and it enables the bi-
cycle to decompress on bumpy roads. (Which
is in fact a definitely positive feature.) You
should choose a spring stiffness with which
this negative suspension travel takes up around
30% of the overall suspension travel.This value
usually provides a very comfortable ride on
your fully suspended recumbent bike designed
by HP V
ELOTECHNIK
.