The KONTRONIK PYRO 750-50L
motor before its installation.
The power system pinion
assembly should be smooth
after tightening the pinion nut.
main shaft, you will set the proper gear
mesh. The manual recommends two
layers of plastic. I used one of the parts
bags, which worked fine. When you
insert the lower socket-head bolt that
retains the main shaft, it should be snug,
but do not over-tighten. This could put
additional stress on the gear.
The final part of this assembly is to
install the main shaft collar. You should
pull upward on the main shaft while
tightening the setscrews. JR has included
shims in case there is any additional play.
Swash Servo and Swashplate
The Forza 700 servo mounts are
adjustable fore and aft to accommodate
different servos. When your servos are
installed, center your servo horns. If you
have not purchased them, I recommend
the JR clamping-style servo horns for
the Forza 700 kit. They make servo
setup and installation a breeze. JR
includes a swash alignment tool that
slides under the swashplate.
swashplate is a red,
bearings, it is as
smooth as you
Balls and link rods
are attached as
instructed. The ball
links are smooth
and do not need
any sizing. They
are tight to pop on,
but when installed,
they are as smooth
The center hub
lines up as pictured and bolts on with a
large shouldered bolt. Make sure this is
snug, but do not over tighten because it
will place stress on the materials.
Main Blade and Rotor Head
The washout arm assembly is
simple. The main blade holders have
preinstalled thrust bearings. One nice
feature during this assembly is the
smooth main grips that moved freely
after installation, which is a sign of
I would not typically discuss
rotor head linkages, but my thumbs
mentioned it would be a good idea.
The linkages from the main grips to the
follower arms are tight—and I mean
tight—to screw onto the linkage rods.
Standard linkage rod tools do not work
because the JR plastic is too thick. I
worked until my thumbs said “no more”
and began using two ball-link pliers to
screw the linkage rods together. The
plastic is firm and, if you are careful, you
can use this method without creating
Measurements for ball ends and
placement of tail rod guides are true
to the manual. I used J-B Weld for my
installation. This is the best method
for your tail rod. The torque is already
assembled and inserted, so this step is
Prior to the tailboom insertion,
install your rudder servo. You have
more direct access before inserting the
boom. Inserting the tailboom in the
main frames is easy, but you can only
attach the tail box after the boom is
inserted in the fiber-reinforced polymer
(FRP) rear body. The FRP rear body
makes the boom assembly rigid, and
with the increased visibility, this is a
great addition to the Forza 700. Do not
overtighten the screws attaching the
FRP body because you can crack the
Attaching the tail can only be
completed after inserting the boom
into the FRP-ready body. The JR tail
assembly is a work of art and is as
smooth as you can expect.
Battery Plate, Electronics, Canopy
The battery tray is a great design with
a lock in the front to ensure that your
batteries stay in place. I did encounter a
problem with the clipping mechanism.
Model type: 3-D 700-size flybarless
Skill level: Beginner to advanced
Main rotor diameter: 61. 4 inches
Tail rotor diameter: 11. 3 inches
Weight: 11 pounds ready to fly
Length: 52. 4 inches
Width: 8. 3 inches
Height: 14 inches
Gear ratio: T11 10.2:1: 4.72/T12 9.3:1: 4. 72
Tail drive: Shaft
Control system: Flybarless 120° cyclic
TEST-MODEL DE TAILS
Power system: KONTRONIK PYRO 750-50L;
KONTRONIK JIVE Pro 120
Main blades: 716mm rail blades
Tail blades: JR carbon tail blades
Radio system: JR XG14 DMSS with XBus;
JR RG731BX XBus receiver
Flybarless JR TAGS Mini with RAO1L
control unit: Satellite
Servos: Three JR SLS01 QRS on
cyclic; one JR SPG01 QRS on
Battery: Two Pulse 6S 5,000 mAh 45C
(12S 5,000 mAh 45C stick pack)
Flight duration: 4 to 12 minutes
• Excellent power-to-weight ratio.
• Large flight envelope suited for beginners to
• Designed for simplicity of build and repair.
• Computer numeric controlled helical gear
results in a smooth, quiet drive system.
• Smooth and durable torque-tube-driven tail
system with 6mm output shaft.
• Exceptional instruction manual and diagrams.
• Narrow canopy makes wiring tricky.
• Battery tray clip needed its edge beveled.
AT A GLANCE ...
67 Model Aviation DECEMBER 2014