Rotax 125 MAX evo Operating instructions

Repair Manual
BRP-Powertrain GmbH & Co KG
A-4623 Gunskirchen-Austria
www.rotax.com
www.kart-rotax.com
TNr.298061
for ROTAX Engine Type 125 MAX
125 Junior MAX
125 Mini MAX
125 Micro MAX

DK00020.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 INTRO
Page 1
December 01/2010
Chapter: INTRO
GENERAL NOTE
Foreword Before carrying out repair work on the engine, read the Repair Manual
carefully.
If any passages of the Manual are not clearly understood or if you have
questions, please contact an authorized Distribution or Service Center for
ROTAX-kart engines.
Chapter structure The Repair Manual is subdivided into the following chapters:
Subject Chapter
Introduction Chapter INTRO
List of effective pages Chapter LEP
Table of amendments Chapter RV
General note Chapter 1
Maintenance Chapter 2
Engine and Gearbox Chapter 3
Cubic capacity parts Chapter 4
Crank housing Chapter 5
Carburetor and Intake silencer Chapter 6
Centrifugal clutch and Starter gear Chapter 7
Radiator Chapter 8
Exhaust system Chapter 9

DK00020.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 INTRO
Page 2
December 01/2010
NOTES

Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0
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REPAIR MANUAL
BRP-Powertrain
LEP
Page 1
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Chapter: LEP
LIST OF EFFECTIVE PAGES
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chapter page date

Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0
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BRP-Powertrain
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Page 2
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REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 LEP
Page 3
December 01/2010
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DK00021.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 LEP
Page 4
December 01/2010
NOTES

DK00022.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 TOA
Page 1
December 01/2010
Chapter: RV
TABLE OF AMENDMENTS
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DK00022.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX/125 Junior MAX/125 Mini MAX/
125 Micro MAX
Edition 2 / Rev. 0 TOA
Page 2
December 01/2010
NOTES

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 1
September 01/2011
Chapter: 1
GENERAL NOTE
Contents This Repair Manual contains instructions for all the necessary repair and
maintenance work on the ROTAX-Engine Type 125 MAX DD2.
Table of contents This chapter of the Repair Manual contains general and safety informa-
tion concerning the operation of the kart engines.
Subject Page
General note Page 3
Abbreviations and terms used in this Manual Page 5
Safety notice
Safety information
Instruction
Technical documentation
Use for intended purpose
Page 7
Page 8
Page 10
Page 11
Page 12
Technical data Page 13

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 2
September 01/2011
NOTES

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 3
September 01/2011
1) General note
Purpose This Repair Manual is based on information and the state-of-knowledge
of BRP-Powertrain of the product current at the date of issue.
Documentation For additional information on engines, maintenance or parts, you can
also contact your nearest authorized ROTAX®-Engine distributor.
ROTAX
Distributors ROTAX®Authorized Distributors for Kart Engines.
See on the Internet at the official Homepage www.kart-rotax.com.
Engine serial
number When making inquiries or ordering parts, always indicate the engine
serial number, as the manufacturer makes modifications to the engine for
product improvement. The engine number (1) is stamped on the clutch
side housing half. See Figure 1.
Figure 1 K00139
1
1

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REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 4
September 01/2011
NOTES

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 5
September 01/2011
2) Abbreviations and terms used in this Manual
Abbreviations
Abbreviation Description
°C Degrees Celsius (Centigrade)
°F Degrees Fahrenheit
rpm Revolutions per minute
125 MAX see Manual (Type designation)
125 Junior MAX see Manual (Type designation)
125 Mini MAX see Manual (Type designation)
125 Micro MAX see Manual (Type designation)
INTRO Introduction
IPC Illustrated Parts Catalog
hr. hours
OM Operators Manual
kg kilograms
MON motor octane number
nB as necessary
n.a. not available
Nm newton meter
Rev. Revision
ROTAX is a trade mark of BRP-Powertrain GmbH & Co KG
RON Research Octane Number
RM Repair Manual
S/N Serial Number
SI Service Instruction
SL Service Letter
TOA Table of amendments
part no. Part number
VVolt
LEP List of Effective Pages

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 6
September 01/2011
NOTES

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 7
September 01/2011
3) Safety notice
General note Although the reading of such information does not eliminate the hazard,
understanding the information will promote its correct use. Always use
common workshop safety practice.
The information and components-/system descriptions contained in this
Manual are correct at the time of publication. BRP-Powertrain, however,
maintains a policy of continuous improvement of its products without
imposing upon itself any obligation to install them on its products previ-
ously manufactured.
Revision BRP-Powertrain reserves the right at any time, and without incurring obli-
gation, to remove, replace or discontinue any design, specification, fea-
ture or otherwise.
Measure Specifications are given in the SI metric system with the USA equivalent
in parenthesis.
Symbols used This Manual uses the following symbols to emphasize particular informa-
tion. This information is important and must be observed.
NOTES: Indicates supplementary information which may be
needed to fully complete or understand an instruc-
tion.
A revision bar outside of the page margin indicates a
change to text or graphic.
WARNUNG
WARNING
Identifies an instruction which, if not followed,
may cause serious injury including the possibility
of death.
WARNUNG
CAUTION
Identifies an instruction which, if not followed,
may cause minor or moderate injury.
WARNUNG
NOTICE
Denotes an instruction which, if not followed,
may severely damage the engine or other compo-
nent.

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 8
September 01/2011
3.1) Safety notice
General note
This information relates to the preparation and use of ROTAX Kart
engines and has been utilized safely and effectively by BRP-Powertrain.
However, BRP-Powertrain disclaims liability for all damage and/or injuries
resulting from the improper use of the contents. BRP-Powertrain strongly
recommend that any service be carried out and/or verified by a highly
skilled professional mechanic.
Manual This Manual has been prepared as a guide to correctly service and main-
tain all ROTAX Kart engines.
This Manual uses technical terms which may be slightly different from the
ones used in the Illustrated Parts Catalog.
It is understood that this Manual may be translated into another language.
In the event of any discrepancy the German version prevails.
Warning It is your responsibility to be completely familiar with the safety instructions
including warnings and cautions described in this Manual. These warnings
and cautions advise of specific operating and servicing methods that, if not
observed, can cause a serious engine malfunction or cause the engine to
lose power in flight which can result in loss of life, injury or damage to
equipment.
It is, however, important to understand that these warnings and cautions
are not exhaustive. BRP-Powertrain could not possibly know, evaluate
and advise the user of all conceivable ways in which service might be
done or of the possible hazardous consequences of each way.
Safety instruc-
tion In addition to observing the instructions in our Manual, general safety and
accident preventative measures, legal regulations and regulations of any
aeronautical authority must be observed.
Where differences exist between this Manual and regulations provided by
any authority, the more stringent regulation should be applied.
Illustration The content depicts parts and/or procedures applicable to the particular
product at its time of manufacture. It does not include dealer modifications,
whether authorized or not by BRP-Powertrain, after manufacturing the
product.
WARNUNG
WARNING
Non-compliance can result in serious injuries or death!

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 9
September 01/2011
Locking devices Locking devices (e.g. locking tab, self-locking fasteners, etc. ) must be
installed or replaced with new ones, where specified. If the efficiency of a
locking device is impaired, it must be replaced.
Torque wrench
tightening
Torque wrench tightening specifications must be strictly adhered to.
WARNUNG
NOTICE
If not specified otherwise, the threads are not lubricat-
ed when fastened.

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 10
September 01/2011
3.2) Instruction
General note Engines require instructions regarding their application, use, operation,
maintenance and repair.
Technical documentation and directions are useful and necessary comple-
mentary elements for personal instructions, but can by no means substi-
tute theoretical and practical instructions.
These instructions should cover explanation of the technical context,
advice for operation, maintenance, use and operational safety of the
engine.
Safety notice In this technical Manual passages concerning safety are especially
marked. Pass on safety warnings to other users!
Modifications Non-approved modifications to the engine and associated components
likewise releases BRP-Powertrain from its warranty obligations.
Accessories This engine must only be operated with accessories supplied, recom-
mended and released by BRP-Powertrain. Modifications are only allowed
after consent by the engine manufacturer.
Spare parts
Tools
Engine A fundamental requirement is that on removal of the engine for repair or
maintenance purposes it should be secured on the Special Tools part no.
877930 (Trestle support) and part no. 676052 (Trestle adapter) obtainable
from BRP-Powertrain.
WARNUNG
NOTICE
Spare parts must meet with the requirements defined
by the engine manufacturer. This is only warranted by
use of GENUINE ROTAX spare parts and/or accesso-
ries (see IPC) or suitable equivalent in the manufactur-
er‘s opinion otherwise, any limited warranty by BRP-
Powertrain is null and void (see Warranty Conditions).
Spare parts are available at the authorized ROTAX
Distribution- and Service Center.
Any warranty by BRP-Powertrain becomes null and
void if spare parts and or accessories other than GE-
NUINE ROTAX spare parts and/or accessories are
used (see latest Warranty Conditions).
WARNUNG
NOTICE
In principle use only tools and appliances which are
either cited in the Manual or in the Illustrated Parts Ca-
talog.

DK00023.fm
REPAIR MANUAL
BRP-Powertrain
Effectivity: 125 MAX DD2
Edition 2 / Rev. 0 Chapter 1
Page 11
September 01/2011
3.3) Technical documentation
General note The information contained is based on data and experience that are con-
sidered applicable for skilled mechanics under normal conditions.
Due to the fast technical progress and fulfilment of particular specifica-
tions of the customers it may occur that existing laws, safety prescrip-
tions, constructional and operational regulations cannot be transferred
completely to the object bought, in particular for special constructions, or
may not be sufficient.
Status The status of the Manuals can be determined with the aid of the table of
amendments. The first column indicates the revision state.
Replacement
pages Furthermore the Manual is constructed in such a way that single pages
can be replaced instead of the complete document. The list of effective
pages is given in the chapter LEP. The particular edition and revision
number is given on the footer of each page.
Reference Any reference to a document refers to the latest edition issued by
BRP-Powertrain, if not stated otherwise.
Illustrations The illustrations in this Manual are mere sketches and show a typical
arrangement. They may not represent in full detail or the exact shape of
the parts which have the same or similar function. Therefore deduction of
dimensions or other details from illustrations is not permitted.
NOTES: The Illustrations and Documents in this Manual are stored
in a document data file/graphic data file and are provided
with a consecutive irrelevant number.
This number (e.g. 00277) is of no significance for the con-
tent.