Troubleshooting guide

Scaling the Kart

The following steps are very important to the scaling accuracy of your kart:

Use digital scales for highest accuracy and repeatability.

Be certain the floor is level. If necessary, place shims under the appropriate corner scales.

This is very important.

Set caster and camber evenly on both sides of the kart.

Set spindle heights evenly on both sides of the kart.

Set toe (always after setting caster, camber and ride height).

Check that tire pressures are at race settings (15-17psi should be fine).

Fill the fuel tank to halfway.

Secure the steering wheel to the center position.

Carefully place the kart on the scales and secure the brake pedal with a bungee to the bumper.

Have the driver sit in his/her normal driving position (hands on the wheel) before the scale

reading is taken. Try to avoid any unnecessary movements of the head or arms.

Be sure to properly document all corner weights before making any changes.

Adjusting Kart Weight

If necessary after scaling the kart, adding weight can aid in perfecting the distribution. With many

drivers, weight usually has to be added anyway. A good general rule for the location of added ballast

weight is to center the weight somewhere on the seat, given that the mass of the kart needs to be

centered as best as possible. Adding weight to the seat aids this. The area under the front edge of the

seat is excellent for a 4-5 pound weight. Generally the weight should be added as low as possible.

Lead shot in the frame should not be used. Be sure to either double-nut or safety wire the lead weight

bolt securely to the kart so another driver doesn’t hit it at 70mph.

If the driver does not need to add weight, they are probably at the weight limit of their class. Drivers in

this case are often reluctant to add weight just to improve their weight distribution. However, there is

evidence that adding the weight to refine the weight distribution is more beneficial than leaving the five

or ten pounds off the kart.

After the correct distribution is achieved, the driver should make one more observation The front

wheels should weigh within five pounds of each other. The same situation applies to the rear wheels

too. If this is not the case, re-check the factors effecting weight distribution given above and re-scale

the kart. If the problem still exists, you may have to re-adjust the seat and start the process all over

again.

Tweaking the Chassis

If the side to side weights are outside an allowable range, you may need to “tweak” the frame in order

to achieve proper side-to-side weight distribution. There are several means of adjusting the chassis.

The following is one method.

If the front corner weights are not equal (by more than 5 pounds), place the kart on a flat floor. Place

an extra wheel or a floor jack under the front wheel (or king pin) that is heaviest. Then, with someone

standing on the rear wheels (leaning against the seat), push down on the light side of the kart sticking

up in the air. This should be repeated until both front wheels carry the same weight. Once the front

has evened-out, the rear should also.