When tuning the FireHammer, make sure that you have
equal lengths from one side to the other on the shocks,
camber rods and steering rods. Also, make sure to have the
shock pre-load adjusters at the same setting from left to
right. They do not have to be the same front to rear.
CASTER
Caster refers to the
angle at which the
kingpin is at in relation
to the surface when
viewed from the side.
0-degrees of caster
means that the kingpin
is straight up and down.
CAMBER
Camber refers to the angle at which the tire and wheel ride
in relation to the ground when viewed from the front or rear.
Negative camber is when the tire and wheel lean inward and
positive camber is when the tire and wheel lean outward.
Typically you want 0 to -2 degrees of camber. Never put in
positive camber. Make sure that both sides are equal.
FRONT AND REAR TOE-IN AND TOE-OUT
Toe-in and toe-out refers to the angle at which the tire is at
when view from above. Toe-in increases stability under
acceleration. However, toe-in also decreases steering when
entering a corner. Toe-out will increase steering into corners,
but will decrease the overall stability during acceleration. The
front typically is set-up with 0 to -2 degrees of toe-in.
RIDE HEIGHT
The ride height of the FireHammer affects how it jumps and
handles. The ride height of the FireHammer is adjustable
through the threaded pre-load adjusters on the shock
bodies. To measure the ride height of the FireHammer, set
the buggy up as if you are ready to run. Push the front of the
buggy down all of the way and release it. When the buggy
returns the front arms should be parallel with the surface.
The rear ride height is set up the same except that the drive
shafts are parallel with the surface. Lowering the front ride
height will increase steering response due to more weight
on the front wheels. Lowering the rear ride height will
increase rear traction and reduce steering response due to
more weight on the rear wheels.
FRONT SHOCK ADJUSTMENT
Moving the tops of the shocks out will increase steering and
quicken reaction. Moving the tops of the shocks in will result
in slower steering reaction, but will be smoother over bumps.
REAR SHOCK ADJUSTMENT
Moving the tops of the shocks in will result in more traction
in the corners and smoother handling over the bumps.
Moving the tops of the shocks out will give the buggy more
steering and better ability to handle large jumps.
SHOCK OILS AND SHOCK SPRINGS
Many different combinations can be used between the
shock oils and shock springs. Some basic guidelines when
setting up the FireHammer are that if the rear end is stiff it
will give the buggy more steering and less rear traction.
Hardening the front will result in less steering and more rear
traction. (Changing the position of the threaded shock pre-
load adjusters results in ride-height change. It does not
change the spring tension).
Thinner shock oil makes the shock react faster, but makes
the buggy less stable and may cause the buggy to bottom
out over large jumps. Thicker shock oil makes the buggy
smoother over large jumps and in straights, but less reactive
over rough sections.
1˚ Toe-In
1˚
1˚
Wheels pointed towards each other
TUNING GUIDE
7
