Developed To Win...

Adjustment

Specifics

Handling Effect

Front Track Width

Wide

A wide front track will add grip to the front end.  It will also help the kart rotate in the corner due to the "jacking effect" which occurs when the wheels are turned into a corner.  This concept can be seen easily when the karts is on the stand.  By turning the steering wheel, you can watch as the inside tire goes down and the outside tire goes up.  The "weight jacking" allows the inside rear wheel to lift up much easier, allowing the kart to rotate as it is powered by the outside rear tire.  The wider the front track width, the most pronounced the "jacking effect"

Narrow

A narrow front track width will result in less scrub, providing better turning up front.  A loss of the "jacking effect" is the trade-off.  While the front will track around the better by getting more grip, without the lifting of the inside rear wheel, the kart will not rotate in the corner.

Front Ride Height

High Frame

To raise the chassis, lower the spindle in its carrier by moving the washers from the bottom to the top.  By raising the front ride height, you effectively raise the center of gravity in the kart and will be increasing side bite on the tire, making it grip harder.  If you go too high however, the raised CoG will make the kart "bicycle" or pick ups both inside wheels.

Low Frame

To lower the chassis, raise the spindle in its carrier by moving the washers from the top to the bottom.  By lowering the front ride height, you will take side bite away from the tires and allow them to slide instead of grip.  This will decrease the grip in the front-end.

Front End Alignment

Toe-Out

Toe-out is recommended for sprint track applications.  It helps the kart on turn-in although it will also make the kart wander slightly on high-speed straight-aways.

Zero

Zero toe can be used on road race tracks in an effort to gain top-speed.

Toe-In

Toe-in is not normally used on a kart but can be brought into play in special circumstances and conditions.

Tire Pressure

Higher

Increasing tire pressure will help the tire build hear quicker, providing increased grip in less laps.  Too much pressure will heat the tires up too quickly and will result in excess tire wear in a short amount of laps.  Finding the middle ground between heat/grip and tire wear is the key.  Try to get the pressures so that they will grow no more than 2-3 lbs. during a session.

Lower

Lower tire pressure will not allow the tire to come up to temperature as quickly and will likely result in a loose condition until the tires hear up and begin to grip.

Caster

Positive

Caster is normally adjusted using an off-set adjustment pill at the top and/or of the spindle carrier.  The spindle can be tipped forward or back simply by turning the adjustable pill.  To add or "turn" caster into the chassis, turn the pill so the the offset hole is towards the back of the kart, leaning the spindle back.  This will give you more front end grip.

Negative

Taking caster out of the chassis is accomplished by turning the adjustment pill so the offset hole is pointing forward.  This will stand the spindle up and will take grip out of the front of the kart.   

Torsion Bars

Assorted

Torsion bars are essentially removable frame rails that are clamped to the chassis to control the amount of flex that a chassis has.  By removing these bars, you can make the chassis stiffer or softer depending on the conditions.

Seat Struts

Assorted

Seat struts are bars mounted on the sides of the seat to the bearing hangers.  They take advantage of the largest mass in the kart - the driver - utilizing this weight, transferring it straight to the rear tire, planting it hard.  The will give you more rear grip.

Axle

Soft

A soft axle will flex more under load, absorbing the energy transferred during cornering, taking it away from the tires.  The absorption will not make the tries grip as hard and will therefore take grip out of the rear.

Hard

A hard axle will not flex like the soft axle, forcing the energy to the tires which will in turn make them work harder, not allowing them to slide.  This will provide more grip in the rear of the kart.

Hubs

Long

Different lengths of hubs affect chassis in a similar fashion to the different flex rates of an axle.  The assorted lengths of hubs will control the flex of the axle.  Therefore, long hubs will make the axle stiffer on the segment of the axle outside the bearing hangers.  This will make the tires bite and will result in increased rear grip, similar to a stiff axle.

Medium/Short

Medium and short hubs will work conversely to the long hubs.  The shorter the hubs the more the axle will flex.  Increased axle flex means increased energy absorption which will allow the tires to slide.  By going to smaller hubs, you will decrease the amount of rear grip.

Rear Track Width

Wide

When discussing grip in relationship to track width, there are boundaries when going too far which can cause the kart to become loose.  Within limits, a wider rear track will be more stable and will provide more grip.

Narrow

A narrow rear track will be less stable at speed and will give the chassis less rear grip.  

Condition

Possible Causes

Adjustments

Entry Push

Too Much Rear Grip

Softer axle
Shorter hubs
Lower rear ride height

Not Enough Front Grip

Widen front end
Add caster
Raise front ride height
Move seat forward

Exit Push

Kart Not Rotating

Softer axle
Shorter hubs
Lower rear ride height

No Jacking Effect

Widen front track width
Add caster

Loose on Entry

Too Much Front Grip

Lower front ride height
Narrow front end
Take out caster
Move seat back

Not Enough Rear Grip

Stiffer axle
Longer hubs
Increase rear ride height
Add seat struts

Brake Bias Problem

Dial in more rear brake (if not locking rears)
Dial in more front brake (if locking up rear on entry)

Loose on Exit

Not Enough Rear Grip

Widen rear track width
Stiffer rear axle
Longer hubs
Add seat struts