HP Velotechnik trikes - Manual (Page 80)

Front suspension elements
76
by choosing another steel spring with different
spring rate.
Varying the number of elastomers and their
relation to the number of spacers inside the
steel spring changes the area of operation as
well as the suspension characteristic. It is al-
lowed to have one or more blank spaces out
of the five spaces available for elastomers or
spacers. In this case the load during the first
part of the travel is only taken by the steel
spring and the elastomers only affect the sus-
pension after the travel of the blank spaces is
used up.
Caution! Do not install more
than two spacers in one strut, otherwise
the full suspension travel can not be
reached. Spacers should always be installed
at the top of the stack inside the spring to
give room for the screw in the top cap.
The setup must be similar in both suspen-
sion struts of your tricycle.
If you use your full suspension tricycle under
different conditions and changing loads as well
as on good and bad surfaces, a setup with a
progressive characteristic for the whole travel
is recommended to get a comfortable suspen-
sion under all conditions of use. The elastom-
ers support the steel spring from the
beginning. By changing the relation between
the number of elastomers and number of
spacers, you can influence the suspension
characteristic and the maximum force the
strut can bear before it bottoms out.
Examples in the diagram are the curves nr. 1
and nr. 2 which show the standard setups.
They feature moderate progression and in-
creased maximum load compared to a single
steel spring. (Setup: spacer-spacer-elastomer-
elastomer-elastomer)
Will your tricycle always face the same load
and only high quality roads, for example, you
may tune your suspension characteristic to a
more linear behaviour in the first two thirds
of travel and a high progression in the remain-
ing third. The linear part provides very high
comfort. The progression at the end prevents
the strut from frequently bottoming out due
to unusual high loads.
A characteristic like this (3) can be achieved
by a steel spring which is responsible for tak-
ing all the load at first and will be supported
by only a few elastomers towards the end of
travel. (Example setup: empty-spacer-spacer-
elastomer-elastomer)
To exchange elastomers or spacers, the end
cap and the preload adjuster (which is under
tension) must be removed. Having done so,
the steel spring and the inside elastomers and
spacers can be taken out. The lower support
of this suspension package is an axial bearing
which consists of three parts. This bearing or
its parts may stick to the spring (caused by lu-
bricant). Make sure this axial bearing is
mounted under the spring in the correct or-
der (washer-bearing-washer) during reassem-
bly. If there are elastomers left in the strut, a
thin needle pricked into will help to remove
them. Now the springs, elastomers, and spac-
ers can be recombined. When screwing in the
preload adjuster disc, make sure it is aligned
straight. It must be screwed in against spring
force, therefore the assistance of a second
person might be asked.