Go-kart Chassis's Design and Construction Based on Theoretical and Experimental Findings

8/11/2019 Go-kart Chassis's Design and Construction Based on Theoretical and Experimental Findings

1/24

Go-Kart s Design

And

Construction

Based On Theoretical And Experimental Findings

By

Ho

Yoong

Chow

Thesis

submitted

to

the

Faculty

of

Engineering,

Universiti Malaysia Sarawak

As

a

partial

fulfillment

of

the

requirement

for

the

Degree

of

Bachelor

of

Engineering

with

Honours

(Mechanical

Engineering

and

Manufacturing

System)

2001


2/24

Acknowledgements

I would like to express my deepest appreciation for those who helped me in

making

this

paper such a

success.

Without

their

support and

assistance

this

paper

would

not

be

completed

as

it is

and

in

such

short

term.

First

and

foremost

I

would

like

to thank

my supervisor

Mr. Syed

Tarmizi

Syed

Shazali

who

had

provided

me

a

truly

understanding of

scholarship

and

support

along

this

paper.

Next

my

fellow

group

mates

Mr.

Tan

Tang Chin Mr.

Fam Kueh

Szue

and

Mr. Rowdy Ignatius

who

have been

very

cooperative and supportive

to

rne.

I

would

like to

say

thank

to

our

CNC

laboratory

technician

Mr. Masri

b.

Zaini

and

Mr. Rhyier

a/k

Juen

who

supplement me

the

skill

of operating

and

handling

the

machine

tools

and

devices.

By

this

opportunity

I

would also

like

to thank

Mr.

Opec Kadri

owner and

Managing

Director

of

Cosama

Sdn

Bhd

and

Mr. Wan Azlan

Shah lecturer

of

Polytechnic Kuching who generously provided me with knowledge for building a

go-kart.

Finally

I

would also

like

to thank

my

family

fellow

friends

and

those

involved

in

completion

of

this

project and

documentation.

Ho

Yoong Chow

UNIMAS 2001

iv


3/24

Table Of

Contents

Letter

of

Approval

Approval Sheet

Project Title

Acknowledgements

Table

of

Contents

List

of

Figures

List

of

Tables

List

of

Graph

Abstract

Abstrak

1

Introduction

1.1

History

of

Go-Kart

1.2

Go-Kart Today

and

Future

2

Literature

Review

2.1

Introduction

2.2

Chassis

Design

2.2.1

Frame Construction

2.2.2

Unit-Body Construction

2.2.3

Space

Frame Construction

2.3

Platform

2.4

Chassis

Materials

2.4.1 Galvanized Steel

2.4.2

High-Strength

Steel

2.4.3

Chrome-moly

2.5 Evaluating Go-Kart s Chassis

2.5.1

Chassis

Squareness

2.5.2 Length

Pages

i.

ii.

iii.

iv.

V.

viii.

X.

XI.

XI1.

1

1

2

4

4

4

5

7

8

8

9

10

10

11

11

11

12

V


4/24

2.5.3 Steering

Position

Alignment

2.5.4 Kart Straightness

2.5.5

Other

Jobs

2.6 Basic

Go-kart s

Chassis

Theories

2.6.1 Frame

Construction

2.6.2 Side Bite

2.6.3 Torsion Bars

2.6.4 Ackerman Steering

2.6.5

Kingpin Inclination

2.6.6

Spindle

2.6.7

Scrub Radius

2.6.8

Caster

2.6.9

Caster Stagger

2.6.10

Camber

2.6.11

Toe-in

3

Methodology

3.1

Data

Collection

From Research

3.2

Data

Collection

From

Interview

3.3

Mathematical

Analysis

3.4 Chassis Design Generation

3.5

Go-Kart

Construction

3.6

Initial

Chassis Setup

3.6.1

Chassis Baseline

3.6.2

Chassis

Alignment

3.6.3

Initial Setup

3.6.4 Rear Axle

3.6.5

Rear

Axle Mounting

3.6.6

Spindle

Installation

3.6.7

Front

And

Side Bumper

3.6.8

Seat

Installation

3.6.9

Floor

Pan

vi


5/24

3.6.10 Weight

Distribution

4

1

3.7

Chassis

Material Testing

45

3.8

Evaluation Of

The

Final Product

47

4

Results And Discussions

48

4.1

Frame

Design

48

4.2

Chassis

Baseline Measurements

49

4.3

Kingpin

Inclination

of

Chassis

53

4.4

Spindle

Angle

53

4.5 Scrub Radius 54

4.6

Caster Setting

55

4.7

Caster

Stagger

56

4.8

Camber

56

4.9

Weight

Distribution

57

4.10 17

Degree

Method

59

4.11

Chassis Material

Evaluation 60

4.12

Photo

Gallery

65

5

Conclusion

And Recommendations

71

References

74

Appendices

A-1 Sample Go-Kart Chassis From Specter Racing Chassis

A-2

Sample

Technical Drawing

A-3

Go-Kart build

by

students

of

Polytechnic Kuching

A-4

Go-karts

found

in

Cosama

Sdn.

Bhd.

A-5 Kart Setup Output

A-6 Tensile Properties For

Some

Engineering

Metals:

Engineering

Properties.

A-7

Technical Drawings

of

MechTech-Initial

vii


6/24

List Of

Figures

Pages

1.1 One of karting pioneer, Don Boberick riding the first 2

Rathmann Xterminator

prototype

kart.

(Extracted

from

http:

//www.

vintagekarts.

com)

1.2

Don

driving

the

Drone

at

the

Rose

Bowl

parking

lot

1957.2

(Extracted from

http: //www.

vintagekarts.

com)

2.1

Ladder frame

of a

common

vehicle.

(Extracted

from

5

Automotive Chassis Systems,

p.

2)

2.2 Perimeter

frame

of a

common

vehicle.

(Extracted

from

6

Automotive

Chassis

Systems,

p.

2)

2.3

(a)

Unitized

construction,

the

small

frame

members are

for

7

support

of

he

engine

and suspension components.

Many

vehicle

would

attached

the

suspension components

directly

to the

reinforced sections

of

the

body

and

do

not required

the

rear

frame

section;

(b)

separate

body

and

frame

construction.

(Extracted

from Automotive

Chassis

Systems,

p.

2)

2.4

Torsion bar

of

a common

car.

17

2.5

Results

of

Ackerman

Steering

test taken

at various angles of

18

the

steering.

2.6

Common Ackerman

steering

of

a

go-kart.

19

2.7

Kingpin

inclination. 20

2.8

Scrub

radius.

21

2.9

Torque

arm caused

by

scrub radius.

22

2.10 Caster Angle. 23

2.11 Camber.

24

2.12

Toe-in. 25

3.1

Sample

chassis

found

in

Cosama Sdn.

Bhd. 27

3.2

Go-kart built

by

students

of

Polytechnic

Kuching.

28

viii


7/24

3.3

Kart Data for Windows

95/NT

used

in

calculating

the

weight

29

distribution

on a

go-kart.

3.4

Kart

Setup

by Kyle Davidson.

30

3.5 Designing

software

for

generating

drawing

of

the

new

31

chassis-

AUTOCAD

R14.

3.6

Worktable.

32

3.7

The

worktable

specially

constructed

for

building

the

chassis.

33

3.8

Process

of

heating

up

the

steel pipe

for

bending

process.

34

3.9 Bending process of the frame. 34

3.10

Figures

showing

steel

pipes which

have been

welded

35

together

to

make

up

the

outer

frame

of

the

chassis.

3.11

Completed

frame.

36

3.12

Weight distribution

test

without

driver).

43

3.13

Weight

distribution test

with driver).

43

3.14 17 Degree Method testing. 44

3.15 17

Degree

Method

testing.

44

3.16

G. I.

pipe

testing

setup.

46

4.1

Spindle

Angle.

53

4.2

Caster

angle of

the

front

right

wheel.

56

4.3

Results

obtained

from

Kart Data

2000.58

ix


8/24

List Of

Tables

Pages

4.1 Weight distribution of the go kart. 57

4.2

Results

of

17

Degree Method

testing. 59

4.3

Result

of

G. I.

pipe

testing.

60

4.4

Modulus

of

Elasticity

61

List Of Graph

Pages

4.1

Deflection

versus

Load.

61

X


9/24

Abstract

The

best

way

to

evaluate a

functioning

go-kart would

be

testing its

performance

under

various

conditions

and

points.

Therefore,

a new

go-kart

called

MechTech-

Initial

was

presented

in

this

report.

Mech Tech

-Initial

was constructed

based

on

the

common go-kart

size

found

in

the

market

but

with

slight

difference

in the

frame

design. MechTech-

Initial s

chassis

was

built

using steel

pipes,

bent

and welded

together,

with

consideration

to the

position

of

engine position,

braking

system,

steering

system,

seat

position

and

many

more.

Other go-kart s components such as engine, seat, steering wheel, brake

system,

bumper

and wheels are

mounted

to the

chassis

to test the

performance.

The

chassis

dimensions

were

taken

for further

testing

and

future

reference.

Among

the

tests

applied are

weight

distribution

on

each

wheel, and

17

degree

method.

xi


10/24

Abstrak

Cara

yang paling

berkesan

untuk

menguji

persembahan

sebuah

go-kart

adalah

dibawah

pelbagai

keadaan

dan

kedudukan. Maka,

satu

go-kart

yang

diberi

nama

MechTech-initial

telah

dihasilkan

untuk

laporan ini.

Mech

Tech-

Initial

telah

dibina

berdasarkan

ukuran go-kart

yang

lazimnya

dijumpai di

pasaran

dengan

sedikit

perbezaan

dalam

rupabentuk

rangka.

Cesi

Me

ch

Tech

-Initial

dibina dengan

menggunakan

paip-paip

besi

yang

dibengkok

dan

dikimpalkan

bersama,

dengan

mengambilkira

kedudukan

enjin,

system

pembrekan,

roda

steering,

kedudukan

kerusi

dan

sebagainya.

Komponen-komponen

go-kart yang

lain

seperti

engine,

kerusi,

roda

steering,

brek, bampar

dan

roda

kemudiannya

dipasang ke

atas

cesi

untuk

menguji

persembahannya.

Dimensi

cesi

diambil

secara

teliti

untuk

tujuan

kajian

lanjutan

dan

rujukan

masa

depan.

Antara kajian

yang

dijalankan

adalah penyebaran

berat

pada setiap

roda

dan

metod

17

darjah.

X11


11/24

1

Introduction

With

the

completion

of

Sepang

International

Formula

One Circuit,

automobile

racing

has

become

one

of

the

most

popular

sports

among

Malaysian.

Consequently,

go-karting

begin

to

gain more attention

as

there

is

no

age

limit

to

this

sport.

Furthermore,

go-kart nowadays requires

very

low

investment,

making

it

affordable

by

most

people

to

either

purchasing

from

public

retailer

or constructing

one

in

a

workshop.

1.1 History of

Go-Kart

Go-kart

technology

has been

widely

developed

since

the

introduction

of

wheels.

But,

it

was not

fully

implemented

in

racing activity

until

the

past

three

hundred

years

in

America.

The first

go-kart

was

simply

a

cart

consisting of wheels

and

handles

jointed

together

as children

pushed

from

behind

when

learning

to

walk or a

four-wheeler

platform

where children

can

sit

on

it

while

another

push

the

kart

around.

Go-kart

was

invented in

California

by

Art Ingels

and

Lou Borelli

using

100cc

mower engines

and strong steel

frames.

Then,

newly

designed

karts

were

beginning

to

gain

popularity

in

Britain

around

the

year

1959-,

960.

Go-kart

has

long

existed

in

our world

whether

used

in

sport

or

recreation.

By

definition

of

International Karting Commission

-

Federation

International

Automobile

CIK-FIA),

a

kart is defined

as

a

land

vehicle

with

or without a bodywork, with 4 non-aligned wheels in contact with the

I


12/24

ground,

two

of which

control

the

steering

while

the

other

two

transmit the

power.

Its

main parts

are

the

chassis

(which

consists of a

body frame

work

that is made up of a set of bent steel pipes that are welded together) with

an

engine,

four

wheels and

tyres

attached on

it.

Figure 1.1

One

of

karting

pioneer,

Don Boberick

riding

the

first Rathmann

Xterminator

prototype

kart. (Extracted

from

http: //www.

vintagekarts.

com)

Figure

1.2

Don

driving

the

Drone

at

the

Rose Bowl

parking

lot

1957.

(Extracted

from

http:

//www.

vintagekarts.

com)

1.2

Go-Kart

Today

and

Future

Go-kart

racing

is

a cheaper and smaller way of

automobile

racing

not

forgetting, a lot safer compared to other motor racing sports such as

2


13/24

Formula

One.

Today, go-kart

racing

is

not

only

practiced

by

adult

hut

the

younger generation.

Allowing

an early

start

on

this

sport,

as

young

as

the

age of

5

or

6

years old. would

he beneficial

as

it is

the most suitable period

for

them to

gain experience

to

be

a

professional

driver

in

the

future.

Practicing

on

go-karting

can

properly expose

the

driver

to the

actual

racing

environment,

training

them

to

be

professional

motor racer

in

various

competitions

such as

Formula

One,

NASCAR,

Indy

racing, and others.

Nowadays,

go-karting

is

as

popular as

it

has

ever

been

with

continued growth

every

year,

and

the

manufacturers

who

have

stayed

with

go-kart

industries

are capable

to

stabilize and

obtain

a

promising market.

However,

the

technology

in

go-karting

seems

to

be

stabilizing

at a stage

even

though

minor

improvement

was

done

on

the

performance.

One

of

the

challenges

in improving

go-karting would

be

building

more standardized

track

for

the

growing

number of

go-kart s

driver.

With

continuous

improvement

in

go-kart

industry

whether

on

go-kart

designs,

equipments, services such as available

tracks,

or

driving

techniques,

this

sport

would surely obtain

a

very

high

ranking

of popularity

in the

near

future.


14/24

2

Literature

Review

2.1 Introduction

Usualiy

a go-kart

driver

or owner

who wants

to

improve

the handling

of

the

vehicle will purchase

the

latest in

wheels,

tyres

and

other

optional

equipment,

but

end up

finding

that

those

things

in

fact

handles

worse.

The

first

stage

in

achieving

a good

handling

kart

that

will provide

the

greatest

percentage

of power

efficiency

is

to

go

right

back

to

basics.

The

chassis

is

the

framework

of any vehicle.

The

suspension,

steering, and drivetrain components (such as engine, transmission, and

final drive

components) are

mounted

to the

chassis.

The

chassis

would

have

to

be

strong

and rigid

platform

to

support

the

suspension

components

(James

D.

Halderman,

Chase

D.

Mitchell, Jr.,

Automotive

Chassis Systems,

2000,

p.

1).

Furthermore,

the

constructions of

today s

vehicles require

the

use of

many

different

materials.

Chassis

of

a go-kart

is

not much

different

from

a normal

car

chassis,

in

fact,

it is

much

less

complicated.

The

different in

size and

weight

make go-kart chassis much

easier

to

design

and

construct.

2.2 Chassis

Design

A

typical

dictionary

definition

of

chassis

usually

includes

terms

such

as

framework on which the body or working parts of a vehicle, radio or

4


15/24

television

are

built

(Oxford

Advanced Learner s

Dictionary,

p.

190).

There

are

three

basic designs

used

today:

frame,

unit-body,

and space

frame

construction.

2.2.1

Frame

Construction

The

frame

construction

usually consists

of

channel-shaped

steel

beams

welded

and/or

fastened

together.

The frame

(chassis)

of

a

vehicle

will

supports all

the

`running

gear

mounted

on

it, including

the

engine,

transmission,

rear

axle

assembly

(if

rear-wheel

drive),

and all

the

suspension

components.

The type

of

frame

construction

that is

referred

to

as

full frame, is

so

complete

that

most

karts

can

usually

be

driven

without

the

body.

Terms

and

label

of

different kind

of

frame

are as

follows:

Ladder Frame

This

type

of

frame

is

common

for

the type

of perimeter

frame

where

the

transversely

(lateral)

connected members

are

straight

across.

Figure

2.1

show

as a

ladder frame

sample

where

viewed

with

the

body

removed.

The

frame

resembled a

ladder

viewed

from

top.

Figure

2.1

Ladder frame

of

a

common

vehicle.

(Extracted from Automotive Chassis

Systems,

p.

2)

5


16/24

Perimeter

Frame

This

type

of

frame

consists of welded

or riveted

frame

members

around

the

entire

perimeter

of

the body Figure 2.2). The frame

members

will

provide support underneath

the

sides as well as

for

the

suspension

and

suspension

components.

::

igure 2.2

Perimeter

frame

of a

common

vehicle.

Extracted

from Automotive Chassis

Systems,

p.

2)

Stub-Type Frame

Stub-type

frame

Figure

2.3)

is

a partial

frame

often used on unit-body

vehicle,

a

type

of

vehicle

construction,

first

used

by

the

Budd

Company

of

Troy,

Michigan, that

does

not

use a

separate

frame.

The body is built

strong enough to support the engine and the power train, as well as the

suspension

and

steering

system.

The

outside

body

panels

are

part

of

the

structure

James D. Halderman, Chase D.

Mitchell,

Jr.,

Automotive

Chassis

Systems.

2000,

p.

495)]

to

support

the

power

train

and

suspension

components.

It is

also called cradle.

6


17/24

I.

i

Figure 2.3

a) Unitized

construction,

the

small

frame

members are

for

support of the engine and suspension components. Many vehicle would

attached

the

suspension components

directly

to the

reinforced

sections

of

the

body

and

do

not

required

the

rear

frame

section;

b)

separate

body

and

frame

construction.

Extracted from Automotive Chassis

Systems,

p.

2)

2.2.2 Unit-Body

Construction

Unit-body

construction

sometimes

referred as

unibody)

is

designed

in

such

a

way

that the

body

is

combined

with

the

structure

of

the

frame.

The

body itself supports the engine and driveline components, as well as the

7


18/24

suspension

and

steering components.

The

body

is

composed

of

many

individual

stamped

steel

panels

welded

together.

The strength of this type of construction lines is in the shape of the

assembly.

The

arrangement

of parts

to

be

jointed

or

formed

not

only

provides

sufficient

strength

to

withstand

high

stress

but

also

the

stability of

the

vehicle

during

any performances.

The

typical

vehicle

uses

300

separate and

different

stamped steel panes

that

are spot-welded

to

form

a

vehicle s

body.

2.2.3

Space

Frame

Construction

Space

frame

construction

is

a

type

of

vehicle construction

that

uses

the

structure

of

the

body

to

support

the

engine

and

drivetrain

as well as

the

steering

and suspension.

The

outside

body

panels are

non-structural

(James

D. Halderman,

Chase D.

Mitchell, Jr.,

Automotive

Chassis

Systems, 2000, p.494)] consists of formed sheet steel used to construct a

framework for

the

entire

vehicle.

The

vehicle

using

this

type

of

framework

is

drivable

without

the

body. It

would

only

uses

plastic

or

steel panels

to

cover

the

steel

framework.

2.3 Platform

The

platform

of

any vehicle

is

its

basic

size

and

shape.

Various

vehicles

of

different

makes

can share with same

platform and,

therefore,

many

of

the

same

drivetrain

and suspension and steering

components.

8


19/24

A

platform

of a unit-body vehicle

includes

all

major sheet-metal

components

that

form

the

load-bearing

structure

of

the

vehicle,

which

include

the

front

suspension

and

engine

supporting

sections.

The

area

separating

the

engine compartment

from

the

passenger s

seat

is

variously

called

bulkhead.

cowl panel,

dash

panel, or

firewall.

The

height

and

location

of

this

bulkhead

panel

to

a

large degree determine

the

shape

of

the rest of the vehicle.

Other

components

of vehicle platform

design

that

affect

handling

and ride are

the

track

and

wheelbase

of

the

vehicle

the

track

of a vehicle

is

the

distance

between

the

wheels,

as viewed

from

the

front

or

rear.

A

wide-

track vehicle is a vehicle with a wide wheel stance; this increases the

stability

of

the

vehicle

especially when

cornering.

The

wheelbase of

the

vehicle

is

the

distance between

the

centre

of

the

front

wheel

and

the

centre

of

the

rear wheel,

as viewed

from

the

side.

Vehicle

with a

long

wheelbase

tends

to

ride smoother

than

vehicle

with

a

short

wheelbase

(James D.

Halderman,

Chase

D. Mitchell,

Jr., Automotive

Chassis

Systems. 2000,

p.

3).

2.4

Chassis

Materials

Most

of

the

automotive components and parts

are

made

of

cast

iron,

such

as

brake

drums

and

rotors, spindles, engine

blocks,

and

many

other

components

including

fasteners.

There

are

different

types

of steel

for

each

component,

which requires

different

strengths

and characteristic

from

the

9


20/24

material.

The

amount

of

carbon

in

steel

is

the

most

important

point

in

determining

the

strength,

hardness,

and

machining

characteristics.

2.4.1

Galvanized

Steel

Galvanized

steel

is

steel with zinc

coating

which

could protect

the

steel

from

corrosion

(rust).

Another

type

of rust-resistance steel

includes

zincrometal, which

is

a

two-coat

bake-on

system using

chromium

oxide

and zinc.

2.4.2

High-Strength

Steel

High-strength

steel

(HSS)

has

been introduced

widely

since

the

mid-

1970s,

as many car

and

light

truck

parts

have

been

built

with

it.

Application

of

HSS is

commonly

in the

sill area

under

the

doors

where

high

strength

is

required, yet

lightweight is

needed.

Other

applications

in

vehicles

are

in

the

bumper

supports and

impact beams

in

doors.

HSS

is

very

hard,

but heating

causes

it

to

lose

much

of

its

strength.

High-strength

steel

is

low-carbon

alloy steel which

consists

of various

amounts

of

carbon,

silicon,

phosphorus, nitrogen,

and

manganese

(Kalpakjian,

Manufacturing

Engineering

and

Technology,

1995,

p.

166).

Body

repair

technicians

should always

follow

manufacturers

recommended procedures

to

avoid weakening

the

structure of

the

body.

1O


21/24

2.5.2 Length

Equalizing

both

sides

dimensions

of

the

chassis

length

is

very

important.

It

can

be

done

by

heating

the

front

axle

and

twist

the top

of

the king

pin

with

the

greatest

lean

back

to

a more

upright

position

to

match

the

other

side.

2.5.3 Steering

Position

Alignment

The

next step

would

be

aligning

the

steering

position.

Firstly,

the

rims

of

the

front

wheels

must

be

machined

so

that the inner

and

outer

diameters

on

both

wheels

are

all

exactly

the

same size.

Then,

it

is

possible

to

use a

straight

edge

to

check

the

front

wheel

alignment.

Centralizing

the

steering

should

be

done

so

as

to

have

the kart

steering evenly

in

both directions,

and

tracking

well

in

a

straight

line.

The

steering shaft

in

most

modern

karts is

offset

to the

brake

side

of

the kart. With the

wheels

fitted, it is

necessary

to find the difference from

the

centre

of

the

steering shaft at

the

steering

yoke

to

the

inside

of each

front

wheel

level

with

the

steering

arm on

the

kingpin.

This

amount of

offset

should

then

be

built into

the

tie

rods when

the

steering yoke

is

at

bottom dead center (idea quoted from http: /akrweb. com/karting). Then,

the

toe

in

and

toe

out

desired

can

be

adjusted

by

equa;

y lengthening

or

shortening

both

tie

rods.

However,

the

straight edge should

first being

placed

across

the

machined wheels

to

check

that

both

are set on

the

same

amount of camber

before

setting

the

toe

in.

Front

wheel alignment

should

only

be done

if

the

camber

is

equal

and

at

the desired

angle.

12


22/24

2.5.4

Kart Straightness

The

kart

should

be

check

if

it is

twisted.

With

the

kart

positioned

on a

flat

floor,

place

the

wheels

and

tyres back

on

the kart

and

with

the tyres

correctly

inflated,

then

using

a set of

scales

lift

each

front

wheel

by

hooking

the

scale

hook

around

the

king

pin.

Then

spin

the

wheel

lifted

and

slowly

lower

the

kart

until

the

wheel

touches

the

floor

and note

the

amount

of lift needed at the point of contact. Each side of the kart should require

the

same

amount

of

lift.

If

this

is

not

the

case,

the

chassis

is twisted. To

correct

the

situation,

place

the

rear wheel

on

the

same

side, as

the

kart

is

light

at

the

front

and

with

someone

standing

on

the

opposite

rear wheel

twist

the

light

front

side

of

the

kart down. This

should

be

repeated until

the

both

front

wheels

carry

the

same

amount

of weight.

Once

the

front

is

even

the

back

will also

be

even

idea

quoted

from http:

//arkweb.

com/karting).

The

rear

axle should

be

check

if it

is

located

central

to

the

chassis.

Firstly,

try

centering

off

the

chassis

tubes

and

then

checking

the

axle

diagonally

with

the tops

of

the

king

pins

to

check

if

the

chassis runs out

of

line

in

the

centre.

If fault

was

found

with

the

diagonal

check

in the

chassis,

it is

best

simply offset

the

axle

slightly.

Once

this

is

done,

the

ends of

the

rear

axle

can

be

used accurately

for

setting

the

position of

the

rear

hubs.

2.5.5 Other

Jobs

With

all

the

previous

4 jobs

done,

some

other minor activities

should

then

be

carried out.

First

clean and oil every

bearing

and moving the chassis

where

necessary

by

removing

it

from

the

chassis.

Make

sure each moving

13


23/24

part

is

in

good

condition

or

otherwise,

replace

it if

doubtful.

Make

sure

that

all

king

pin

bearings,

steering shaft

bearings,

tie

rod ends,

wheel

bearings

and axle

bearings have

a good

fit

and not

sloppy.

Finally,

check

the kart

for

any cracks

and repair where

necessary

before

putting

everything

back

together.

Once

all

the

steps

have

been

completed,

think

about

setting

up

for

a particular class to help setting the engine requirement.

2.6

Basic

Go-kart s

Chassis

Theories

lt

is

the

responsibility

of

each

karter

to

determine his

own

requirements.

It

is

also

the

karters

responsibility

to

stay within

the

sprit and

intent

of

the

rules

of

the

organization

in

which

he

will

be

participating.

(Brian

Martin,

Go-kart Racing-

Chassis Setup,

2000)

Setting

up a good go-kart chassis

requires not

only

the

knowledge

of

basic

theories

but

also

from

past experiences.

Theories

will

help

beginners

in

setting

their

first

go-kart

but

experiences

would

help

further improve it.

Some

of

the

chassis

theories

will

be discuss

in

the

following

section.

2.6.1

Frame Construction

The

most

important

aspect

in

the

frame

of a

go-kart

would

be its

flexibility,

as

it is

most

crucial

during

cornering

in

a

race.

The flexibility

of

the

frame

can be achieved either by using a particular type of material such as

Chrome-moly,

or perhaps

just by

proper

design.

14


24/24

Some

flexibility

is

good

for

a go-kart

and even makes setting

up

easier,

but

over

the time

the

frame

may not

rebound

back

to

its

original

condition. According to most chassis builder,

current

frames in the

market

are

only

good

for

about

18

months

before

replacement

is

needed.

Racing

on

the

same

track

week

after

week

would cause

the

frame

to take

a set,

which

diminishes

its

flexibility. One

of

the

easiest

ways

to

alleviate

this

condition is by running several laps in a backward direction on the same

track.

2.6.2

Side

Bite

Site

bite

is

the

ability

of

the

go-kart

to

stay

stuck

on

the track

without

sliding when going around

a corner.

With

the

correct amount

of side

bite,

the

go-kart would unload

the

inside

rear

tyre

when

taking

a corner which

will reduce

the

effect

of scrubbing

the tyres.

However, too

much

side

bite

would cause a hop or bicycle around the corner or scrub off so much

speed

causing

the

engine will

bog down.

On

the

other

hand, too

little

side

bite

will

cause

the kart

to

be loose.

The design

of

the

go-kart

frame

itself

has

a

lot

to

do

with

how

much

side

bite

it has.

One

good

indication is

by

measuring

the

width

of

the

rear

frame

rails.

A

narrow

kart

would measure

24 to

25

while

a

wider

kart has

27

to

28 ,

measured

at

the

center of

the

frame

rails

Side

bite

is

also affected

by

frame

stiffness.

The

frame is

essentially

a

series

of

torsions

bars

welded

together.

The

shorter

the

bars

and

the

Date post:	02-Jun-2018
Category:	Documents
Upload:	sudersansridhar
View:	219 times
Download:	0 times

Go-kart Chassis's Design and Construction Based on Theoretical and Experimental Findings

Documents