Losi LOSB0020 - Manual (Page 3)

Required Equipment
You will need the following items to operate your new Raminator.
4 AA alkaline batteries for the transmitter
Losi™ Nitrotane™ 20% Sport Fuel. (LOSF0020 or LOSF0120) This is the only fuel that supports the
engine warranty.
Fuel bottle (LOSB5201)
6V Receiver Pack (LOSB9949 or similar)
Tools You Will Find Handy
In addition to the tools included with the Raminator, you will find the following both useful and in some
cases necessary.
• LOSB4603 4-Way Wrench
• LOSA99167 Tuning Screwdriver
• Small flat blade and Phillips screwdrivers
• Needle-nose pliers
• Quality .050”, 1/16”, 5/64”, 3/32”, 1.5mm and 2.5mm hex (Allen) drivers
Engine Break-In and Adjustments
Breaking in your new engine is critical for proper performance. Failure to follow the break-in procedures
can cause damage and shortened engine life. During break-in and when running, always use Losi
Nitrotane 20% Sport Fuel. Although the carburetor is preadjusted at the factory, you must be familiar
with the following adjustments and break-in procedure. If you change fuel or run in dramatically different
environments (hot/cold, high/low elevation, etc.), you will probably have to adjust at least the high speed
needle to prevent overheating and maintain proper performance. Never, under any circumstances, allow
the engine to rev freely with the wheels off the ground.
Break-In Procedure
1.) The first three tanks of fuel should be run with the high and low speed needles noticeably “rich” (see
explanation below). There should be a slight sluggishness and thick smoke when accelerating with the
smoke decreasing as the model gains speed. At speed, there should still be a noticeable trail of smoke
from the exhaust pipe. Run the Raminator on a flat surface in an oval pattern. Ease into the throttle as you
accelerate on the straight sections, easing off as you approach turns—letting the model roll through the
turn before easing back on the throttle. This will also allow you to get a feel for the steering response and
handling characteristics of the model.
2.) You can also break in the engine by placing the model against a wall or fixed object and allowing the
engine to idle through two full tanks of fuel. You may have to lean the low speed mixture (slightly) as
noted below.
Understanding “Rich” and “Lean” Fuel Mixture
Adjusting the carburetor is one of the most critical facets of running a nitro powered RC vehicle. The fuel
mixture is referred to as being “rich” when there is too much fuel and “lean” when there is not enough fuel
for the amount of air entering the engine. The amount of fuel entering the engine is adjusted with high
and low speed threaded needle valves. The low speed needle is located in the front of the moving slide.
The high speed needle sticks straight up at the back of the carburetor. Both feature a slotted head that is
used as a reference and receptacle for a flat blade screwdriver for adjustments. The mixture is made richer
by turning the needle counterclockwise and leaner by turning clockwise. An overly rich mixture will yield
sluggish acceleration and performance with thick smoke from the exhaust. A lean mixture can cause
the engine to hesitate before accelerating or, in some cases, to lose power momentarily after the initial
acceleration.
A lean mixture also makes the engine run hotter than desired and does not provide enough lubrication
for the internal engine components, causing premature wear and damage. It is always advisable to run
the engine slightly rich and never lean to avoid overheating and possible damage.
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