Introduction
The
setup of the Mini 4WD is one of the most important factors that is M4WD
Racing. A setup in one course may not work on another and vice versa. Because
of this, the performance of the racer solely depends on the owners/players
choice of setup.
The
contents shown below will help the enthusiast select the best setup for
a specific track/course.
The
contents below are based from numerous published references in engineering
sciences and physics, and from experiences of the members of Syndicate
and our consultants.
Contents:
FRP's
and Roller Setup and Stability
Motor
and Transmission
Wheels
and Tires
Body
Modifications
FRP
and Roller Setup
FRP
The
purpose of mounting a FRP is to prevent or minimize the damage done to
the chassis by dampening the shock of an impact by absorbing the some of
the force. Also the FRP gives added strength to the chassis thus making
it more durable.
Most
FRPs are also wider than the chassis. This makes the racer wider and can
add stability to the vehicle especially when turning. Extenders are used
to make the FRPs even wider, if needed.
When
installing and FRP, make sure at least 4-6mm of the mounting screw goes
inside the hole in the chassis.
Rollers
For
tracks with many turns, it is recommended that rollers are installed a
bit high, if not stabilizers should be used to prevent the vehicle from
turning over.
It
is especially important to lubricate the rollers to ensure free and smooth
operation. If the rollers had too much resistance or would lock up, in
turning, this would cause slow turning or worse, the racer would turn over
or fly off the turn.
Front
Rollers should have a slight declining angle, down thrust. This would make
the racer more stable when turning.
For
technical tracks, it is recommended that the overall front width, including
rollers, should be wider than the rear. This makes turning easier, more
stable and perhaps faster.
| parallel
width |
move
parallel to the track |
| wider
front |
move
away from the track wall |
| wider
rear |
move
toward the and hug the wall |
| Overall
Dimension |
Stability |
Cornering |
| Narrow |
Bad |
Good |
| Wide |
Good |
Bad |
| Front/Back
Dimension |
Stability |
Cornering |
| Wider
in Front |
Bad |
Good |
| Wider
in Back |
Good |
Bad |
Large
Diameter vs. Small Diameter Rollers
One
of the advantages of large diameter rollers is its larger circumference.
At the same linear speed, the angular velocity of the larger diameter roller
is slower than the small diameter roller. This means that, assuming the
surface contact between the shaft in which the rollers are mounted are
equal and the materials the same, the wear and tear on the smaller roller
is greater than the larger roller.
On
the basis of overall width, it is not much of a deal, since there are adjustable
FRPs and FRP extensions that can compensate.
Motor
and Transmission
The
motor is one of the most important factors in racing. The fastest motor
is not always the best motor. For technical tracks, the selection of the
best motor is critical. But here's a rule of thumb, use the fastest motor
the car can handle for the track. A racer flying off ramps and turns may
not be caused by a fast motor but also be caused by a poor setup.
Gear
Ratio
It
is practically important to consider the ratio of the gears. 3.5:1 simply
means that the motor must turn 3.5 times for a single turn of the driven
shaft. Thus, a 3.5:1 would attain a higher maximum speed than a 4:1 --
using the same motor. But the mechanical advantage of a 3.5:1 gear
ratio is lesser than in a 4:1. Thus, a 4:1 ratio can make the racer accelerate
faster as well as save energy.
| Gear |
Battery
Life |
Acceleration |
Top
Speed |
| 3.5:1 |
Bad |
Bad |
Best |
| 4:1 |
Good |
Good |
Better |
| 4.2:1 |
Better |
Better |
Good |
| 5:1 |
Best |
Best |
Bad |
Selection
of Motor
1.
try running a slower motor first.
2.
if it does not fly or turn over, try a faster motor
3.
do step 2 until racer becomes unstable
4.
try modifying the setup, rollers, brakes, gear ratio etc. and run it using
the second to the last motor used.
--if it is unstable, it means that the latter setup is worse than the original
one, repeat step 4.
5.
try using the faster motor, if it is still unstable repeat step 4. But
if you can't figure out a way to make the
stable, use the last motor and the best setup as experimented on the above
steps.
Wheels
and Tires
There
are several combinations of wheels and tires. Refer to the table below.
| Diameter/Width/Tire |
Top
Speed |
Acceleration |
Cornering |
Shock
Absorption |
Drag |
Stability |
Weight |
Grip |
| Small/Nar/Sponge |
Bad |
Good |
Good |
Bad |
Good |
Bad |
Good |
Bad |
| Small/Nar/Reston |
Bad |
Good |
Good |
Bad |
Good |
Bad |
Average |
Average |
| Small/Nar/Rubber |
Bad |
Good |
Good |
Bad |
Good |
Bad |
Bad |
Good |
| Small/Wid/Sponge |
Bad |
Good |
Good |
Bad |
Bad |
Good |
Good |
Bad |
| Small/Wid/Reston |
Bad |
Good |
Good |
Bad |
Bad |
Good |
Average |
Average |
| Small/Wid/Rubber |
Bad |
Good |
Good |
Bad |
Bad |
Good |
Bad |
Good |
| Lar/Nar/Sponge |
Good |
Bad |
Bad |
Good |
Good |
Bad |
Good |
Bad |
| Lar/Nar/Reston |
Good |
Bad |
Bad |
Good |
Good |
Bad |
Average |
Average |
| Lar/Nar/Rubber |
Good |
Bad |
Bad |
Good |
Good |
Bad |
Bad |
Good |
| Lar/Wid/Sponge |
Good |
Bad |
Bad |
Good |
Bad |
Good |
Good |
Bad |
| Lar/Wid/Reston |
Good |
Bad |
Bad |
Good |
Bad |
Good |
Average |
Average |
| Lar/Wid/Rubber |
Good |
Bad |
Bad |
Good |
Bad |
Good |
Bad |
Good |
Nar
= Narrow, Lar = Large
Batteries
Although
some races may only allow one type of battery, we hope this helps.
