A simple modification I made to the standard Europa throttle cable was to throw
the cable in the trash. You can recover the sheath and use it but the flexible
cable must go. Using a flexible cable in the above application doesn't seem
to make much sense. Cables are intended for tension applications not
compression.
Given the design of the standard throttle housing, kinking of the cable
is permissible, although certainly not desirable. If you recall some time ago
a Europa was lost due to this very issue. On an attempted go-around the pilot
rapidly advanced the throttle causing the cable to kink within the housing
limiting the throttle command. The springs on the carb installed by Rotax are
designed to advance the carbs to "High/Full" throttle in the unlikely event
of a cable failure. The springs were never intended to pull the cable through
the sheathing which is what is required to some extent in the Europa design.
I have utilized a Bowden cable of similar diameter which is specifically
designed
for push/pull applications. For those not familiar with a Bowden cable it
is basically a semi-flexible solid wire cable. I ordered mine from ACS p/n
05-1550.
One end of the cable will need to be modified to accept the Europa throttle
housing/lever. I bent the end of the wire over a cable fitting, ACS p/n
CF2700, to form an eye and Reduxed the wire to the cable fitting. This allows
a bolt to go through the wire end and attach to the throttle lever. The other
end of the cable is attached to the carbs in the original manner.
With the above setup the friction lock can be set to provide more friction than
is possible if using the supplied Europa cable, since the carb return spring
is no longer assisting the advance of the flexible cable and kinking is of no
concern. The throttle stays right were it is set. In fact I rather like the
Europa throttle lever with this configuration as the RPM can set be very
precisely.
I have 150 hours on the plane and it has worked flawlessly since day one.
Erich Trombley
N28ET Classic Mono 914
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