Christa’s first Racer, a Top Kart Go Kart


kart wheels and tires.
The stock cast Top Kart wheels were changed for these lightweight spun 5×5″ DWT wheels.  The spun wheels have more flex that help free up the lightweight Cadet chassis and help it find traction.  The wheel size and tire size are limited by the rules.  The tires are spec as well, YKC compound Bridgestone racing slicks 4.5×6″

Upon inspection it was obvious that Christa was way too small and skinny for the kart and most of the money spent was things to make the kart fit her.  With Christa’s help, the kart was stripped completely down and everything was cleaned and inspected for wear.  The good folks at Empire Karts were very helpful, spending a lot of time answering our question and supplying us with parts.

Top Kart brake
Top Kart uses a hydraulic disc brake made of billet.  The air gap, pedal motion ratio and pedal travel are all adjustable with shims between the caliper halfs as well as the master cylinder activating arm and pedal.  This gives a huge amount of adjustabilty in pedal travel, effort and feel. The billet bearing carrier for the rear axle allows adjustable ride height.  On a kart, higher gives more traction, lower reduces it.  For some reason kart rules say nearly everything must be safety wired so safety wire is everywhere!

The bare frame was inspected for straightness and then was sent out to be stripped and powdercoated.  A smaller padded Tillet C size seat was selected to try to fit Christa to the kart.  The padding helped take up more space to fit Christa better.  Since her legs were many inches from reaching the pedals even with the pedals in the furthest rearward position, a Noonan Racing pedal box was selected to mount the pedals even further backwards.

Top Kart spindel
Compared to cars, karts have really weird steering geometry.  They run a huge amount of Ackerman, caster , scrub radius and kingpin inclination.  This is because a kart depends on chassis lift when turning to control weight transfer on the rear end.  Since a kart has no diff, the tuning of the front geometry is critical to avoid understeer and power wasting bind on corner exit.  On a race kart like our Top Kart, the scrub radius, Ackerman, track width, corner weight, ride height, camber and caster are all adjustable and small adjustments can make for big differences in handling.

A 2010 spec plastic impact absorbing rear bumper was added to comply with the 2010 rules.  New body parts with a new set of factory Top Kart graphics were installed. All worn parts were replaced with new Top Kart parts from Empire Karts.  The rusty exhaust system was sent to Embee Performance to be ceramic coated and new wheels and tires were installed.  The HPV motor needs an external starter like an IRL car and the battery was dead on the started that came with our kart.  Baker Racing supplied one of their gell cell batteries to get it going again.  We decided to upgrade much of the hardware on the kart and new metric high grade hardware was supplied by Password JDM and Baller Bolts.  Once again Christa helped quite a bit with the assembly of the kart so she could learn how to wrench on things as well.

Top Kart hub and axle
On a racing kart the hub and axle is adjustable.  The hub can be moved inboard and outboard to change track.  A kart responds the opposite as a car.  Widening the track reduces traction and making it narrow increases it.  A long hub stiffens the axle and increases traction.  A short hub allows more flex and reduces traction.  The axle comes in three stiffnesses as well.  A stiff axle increases rear traction while a soft axle reduces traction.  This is because of a kart’s unique use of chassis flex and front end lift to get the kart turned.


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