O.S. engine FL-70 Owner's Instruction Manual page 13

Spinner
Since the FL-70 is intended to be
started with an electric starter, the
addition of a spinner assembly for
centering the starter sleeve is desirable. Use a
heavy-duty, well balanced spinner either of
metal or plastic.
SILICONE FUEL LINE
Heatproof silicone tubing of
approx. 5mm o.d. and 2.5mm
i.d. is required
connection between the fuel
tank and engine.
Propellers
The choice of propeller depends on the design
and weight of the aircraft and o the type of
flying in which you will be engaged. Determine
the best size and
experimentation. As a starting point, refer to
the props listed in the accompanying table.
Slightly larger, or even slightly smaller, props
for the
type after practical
than those shown in the table may be used,
but remember that the propeller noise will
increase if blade tip is raised, due to higher
rpm or if a larger-diameter/lower-pitched prop
is used.
Sport & Aerobatic
Trainer & Scale
Warning:
Make sure that the propeller is well
balanced. An unbalanced propeller and/or
spinner can cause serious vibration which
may weaken parts of the airframe or affect
the safety of the radio-controlled system.
DO NOT forget the WARNINGS and NOTES
on propeller and spinner safety given on
front pages.
Reminder!
Never touch, or allow any object to come Into
contact with, the rotating propeller and do not
crouch over the engine when it Is running.
12
12X7, 12.5X6, 13X6
12.5X6, 13X6-7