|RC Cars -> RC Tips ->
Your R/C Electric Motor Faster
Update 2009: List of brushless motors
approved by IFMAR.
Here are tips to help get the most speed out
your brushed stock or modified motors. Let us start of with getting the
most speed out of the stock Mabuchi 540 RS motor.
|Entry level kits usually come with the
Mabuchi 540 RS or the Johnson motor. These are the "stock" and "closed
end bell" type design. You cannot adjust the timing nor change the
brushes to gain more speed.
|The best way to gain power from these
motors is to properly break-in the motor brushes and the bronze
bushings. One quick method to break-in the brushes is by using the
"water dipping" method. Simply dip the motor in a jar of water, then
attached a 3 volt battery supply to run the submerged motor.
|You can make a 3-volt battery pack by
putting two 1.5-volt batteries in series. DO NOT use a battery charger
or electronic speed control (ESC) as a power source for the submerged
motor. You might damage your charger or ESC.
This "water dipping" method will also
the bronze bushings, which will make the armature rotation smoother,
giving you more rpms and power. Let the motor dry out, and put 1 or 2
drops of lightweight oil on the bushings. Now your motor should be 20%
better than before.
Tip: Serious racers in the stock motor
class usually break-in several of these stock motors. They then test
for power by using a dynamometer. The best motors are then used for
racing. This is the reason why some stock motors seem to be faster than
It is easier to get more speed out of
motors, primarily because you can change the brushes and advance the
With modified motors, you can disassemble
entire motor. You can "true" the commutator to make it as round as
possible and remove the carbon deposits left by arcing and the motor
are used to align the
armature properly with the magnets and magnetic field inside the motor
can. Washers prevent the armature from moving back and forth inside the
can, which robs the motor of power. With the proper use of washer, you
can gain power and speed advantage over your competition.
|Brushes play an important role in
providing maximum power. The composition (e.g. silver, copper content)
and the brush "cut" vary. Also there are "hard" and "soft" brushes.
brush - More power, more
- Less power, less commutator wear.
brush - More power, more
torque, less rpms.
- Less power, less torque, more rpms.
|Springs are used in tandem with the
correct motor brush. In general:
springs - More tension, more
amp draw, more torque, less rpm. For off-road and 4wd touring cars.
- Less tension, less amp draw, less
torque, more rpm. For 1/12 on-road pan cars.
that are too soft will cause the brush to bounce around, causing
excessive arcing, and premature commutator wear.
|Adjusting the motor timing will have a
significant impact on performance. In general:
timing - More rpms, less
- Less rpms, more torque.