BRP Rotax 125 JUNIOR MAX evo Operating instructions

ROTAX-KART.COM
REPAIR
MANUAL
125 SENIOR MAX EVO
125 JUNIOR MAX EVO
125 MINI MAX EVO
125 MICRO MAX EVO

BRP-Rotax
REPAIR MANUAL
Chapter: INTRO
GENERAL INFORMATION
Preface 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.
Contents This Repair Manual contains instructions for all the necessary repair and maintenance
work on the ROTAX®-Engine Type 125 MAX evo, 125 Junior MAX evo, 125 Mini MAX
evo and 125 Micro MAX evo.
Symbols used This Manual uses the following symbols to emphasize particular information. This
information is important and must be observed.
mWARNING
Identifies an instruction, which if not followed may cause injury or endanger the
life of the driver, mechanic or third party.
ATTENTION
Denotes an instruction which if not followed may severely damage the engine.
Noncompliance might lead to health hazards under certain conditions.
ENVIRONMENTAL NOTE
Environmental notes give you tips on environmental protection.
NOTE
Indicates supplementary information which may be needed to fully complete or
understand an instruction.
✔Denotes a checking operation
TIP This information gives you additional advice and tips
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NOTES
BRP-Rotax
REPAIR MANUAL

BRP-Rotax
REPAIR MANUAL
Chapter: Chapter 1
GENERAL NOTE
TOPICS IN THIS CHAPTER
Abbreviations and terms used in this Manual..........................................................................................2
Safety ......................................................................................................................................................3
Safety notice.........................................................................................................................................3
Instruction.............................................................................................................................................4
Technical documentation........................................................................................................................5
Use for intended purpose .......................................................................................................................5
Technical data .........................................................................................................................................6
Purpose This Repair Manual is based on information and the state-of-knowledge of BRP-Rotax 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 web at the official Homepage
http://www.rotax-kart.com.
Engine serial
number
If you have any concerns or questions, always keep your engine serial number ready for
questions from your dealer, as the manufacturer makes modifications to the engine for
product improvement. The engine number is stamped on the clutch side housing half. See
Figure 1.
Figure 1.1: Position of the engine serial number
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ABBREVIATIONS AND TERMS USED IN THIS MANUAL
Abbreviations Abbreviations Description
°C Degree Celsius (Centigrade)
°F Degree Fahrenheit
rpm Revolutions per minute
125 MAX evo see Manual (Type designation)
125 Junior MAX evo see Manual (Type designation)
125 Mini MAX evo see Manual (Type designation)
125 Micro MAX evo see Manual (Type designation)
INTRO Introduction
IPC Illustrated Parts Catalog
h hours
OM Operators Manual
kg kilograms
MON Motor Octane Number
n.a. not available
Nm Newton meter
Rev. Revision
RON Research Octane Number
RM Repair Manual
S/N Serial Number
SI Service Instruction
SL Service Letter
part no. Part number
V Volt
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SAFETY
General note Although the reading of such information does not eliminate the hazard, the understanding
the information will promote its correct use. Always take care by conducting manual work
and use safety equipment. The information and components-/system descriptions con-
tained in this Manual are correct at the time of publication. BRP-Rotax, however, main-
tains a policy of continuous improvement of its products without imposing upon itself any
obligation to install them on its products previously manufactured.
Revision BRP-Rotax reserves the right at any time, and without incurring obligation, to remove, re-
place or discontinue any design, specification, feature or other details.
Specifications Specifications are given in the SI metric system with the USA equivalent in parenthesis.
SAFETY NOTICE
General note
mWARNING
Non-compliance can result in serious injuries or death!
Comply with the safety advice of the engine and kart manufacturer.
This information relates to the preparation and use of ROTAX® Kart engines and has
been utilized safely and effectively by BRP-Rotax. However, BRP-Rotax disclaims liability
for all damage and/or injuries resulting from the improper use of the contents. BRP-Rotax
strongly recommend that any service be carried out and/or verified by a highly skilled pro-
fessional mechanic.
Manual This Manual has been prepared as a guide to correctly service and maintain 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 English version prevails.
Warning It is your responsibility to be completely familiar with the safety instructions including warn-
ings and cautions described in this Manual. These warnings and cautions advise of specif-
ic operating and servicing methods that, if not observed, can cause a serious engine
malfunction or cause the engine to lose power which can result in serious injury, damage
to equipment or even to death.
It is, however, important to understand that these warnings and cautions are carefully
checked. BRP-Rotax can not evaluate and advise the user of all conceivable ways in
which service might be done or of the possible hazardous consequences that may occur.
Safety instruction In addition to observing the instructions in our Manual, general safety and accident pre-
ventative measures, legal regulations and regulations of any superior authority must be
observed.
Where differences exist between this Manual and regulations provided by any authority,
the more stringent regulation should be applied.
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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-Rotax, after manufacturing the product.
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.
NOTE
If not specified otherwise, the threads are not lubricated when fastened.
INSTRUCTION
General note Engines require instructions regarding their application, use, operation, maintenance and
repair.
Technical documentation and directions are useful and necessary complementary ele-
ments for personal instructions, but can by no means substitute 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-Rotax from its warranty obligations.
Accessories This engine must only be operated with accessories supplied, recommended and re-
leased by BRP-Rotax. Modifications are only allowed after the exceptional advice or ap-
proval by the engine manufacturer.
Spare parts
ATTENTION
Spare parts must comply with the requirements defined by the engine manufacturer.
This is only warranted by use of GENUINE spare parts and/or accessories (see IPC) or
suitable equivalent in the manufacturer‘ s opinion. Otherwise, any limited warranty by
BRP-Rotax is null and void (see latest Warranty Conditions). Spare parts are available
at the authorized Distribution- and Service Center. Any warranty by BRP-Rotax be-
comes null and void if spare parts and or accessories other than GENUINE spare parts
and/or accessories are used (see latest Warranty Conditions).
Tools
ATTENTION
Use only tools and appliances which are either cited in this Manual or in the Illustrated
Parts Catalog of the relevant engine type for exceptional repair work.
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Engine A fundamental requirement is that on removal of the engine for repair or maintenance pur-
poses it should be secured on the Special Tools part no. 877930 (Trestle support) and part
no. 676052 (Trestle adapter) available at your authorized Distributor or Service center for
ROTAX® Kart Engines.
TECHNICAL DOCUMENTATION
General note The information contained is based on data and experience that are considered applicable
for skilled mechanics under normal conditions.
Due to the fast technical progress and fulfillment of particular specifications of the custom-
ers it may occur that existing laws, safety prescriptions, constructional and operational
regulations cannot be transferred completely to the object bought, in particular for special
constructions, or may not be sufficient.
Status The current edition of the Manual is shown at the bottom of the pages or on the front
cover.
Reference Any reference to a document refers to the latest edition issued by BRP-Rotax, if not stated
otherwise.
Illustrations The illustrations in this Manual are 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 permit-
ted as the scale may not be 1:1.
NOTE
The Illustrations and Documents in this Manual are stored in a database and are
provided with a consecutive number.
This number (e.g. KA_125MAX_001) is of no significance for the content.
USE FOR INTENDED PURPOSE
Safety note
mWARNING
Non-compliance can result in serious injuries or death!
Use The ROTAX Engine Type 125 MAX has been designed and developed exclusively for use
in a Kart. Any other use renders the BRP-Rotax factory limited warranty null and void.
Maintenance and
repair conditions
Use for intended purpose also includes observation of the operational, maintenance and
repair conditions prescribed by the manufacturer. This is a crucial factor concerning the re-
liability of the engine and can increase the durability of the engine.
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TECHNICAL DATA
Engine Type 125 MAX evo / 125 Junior MAX evo / 125 Mini
MAX evo / 125 Micro MAX evo
Bore/stroke 54.00 mm / 54.5 mm
Displacement 125.0 ccm
Nominal power (max.)
125 MAX evo
125 Junior MAX evo
125 Mini MAX evo
125 Micro MAX evo
22 kW at 11500 rpm
17 kW at 8500 rpm
9.6 kW at 7500 rpm
7kW at 7000 rpm
Torque (max.)
125 MAX evo
125 Junior MAX evo
125 Mini MAX evo
125 Micro MAX evo
21 Nm at 9000 rpm
19 Nm at 8500 rpm
13 Nm at 6000 rpm
10.9 Nm at 6000 rpm
Idle speed between 1500 and 2000 rpm
Ignition unit Contactless, (variable) digital coil ignition
Spark plug NGK GR8DI (standard) and GR9DI (optional)
Electrode gap Refer to the valid technical regulations you are partic-
ipating in.
Fuel Super, unleaded fuel
RON (min.) Min. 95 Octane
Cooling Liquid cooling: Cooling circuit with coolant pump inte-
grated in the engine
Flow rate of the coolant pump approx. 22 liters at 11000 rpm
Coolant mixture 100 % Water (distilled). Drain water after operation in
cold condition to prevent freezing.
Coolant capacity Micro / Mini radiator 0.7 liter
Coolant capacity Mini / Junior / Senior 0.5 liter
Engine lubrication Oil-in-gasoline lubrication, synthetic 2 Stroke oil (RO-
TAX XPS KART-TEC Oil part no. 29460 and ROTAX
SYNMAX Oil recommended).
Mixture ratio 1:50 (2 % oil)
Lubrication of the differential drive SAE Engine oil 15W-40
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REPAIR MANUAL
Engine Type 125 MAX evo / 125 Junior MAX evo / 125 Mini
MAX evo / 125 Micro MAX evo
Engine oil capacity 50 ml (for plastic balance gears) / 100 ml (for steel
balance gears)
Engagement speed approx. 4000 rpm
Power transmission from centrifugal clutch to the rear
axle of the kart
roller chain
Chain dimension 7.75 x 4.6 x 4.5
Number of teeth of the drive sprocket 11, 12, 13, 14, 15, 16 teeth
Weight /dry
approx 12 kg
without intake silencer, carburetor, fuel pump, radia-
tor, exhaust and battery
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BRP-Rotax
REPAIR MANUAL

BRP-Rotax
REPAIR MANUAL
Chapter: Chapter 2
MAINTENANCE
TOPICS IN THIS CHAPTER
General note............................................................................................................................................2
Authorized personnel ..............................................................................................................................3
Process advice........................................................................................................................................4
Consumable materials.............................................................................................................................6
Special tools............................................................................................................................................8
Inspection and servicing intervals of the engine components...............................................................10
Contents The information given in the Repair Manual is based on data and experience which are
considered to be applicable for a skilled mechanic under normal working conditions.
Table of contents In this chapter the repair of engine ROTAX® 125 MAX evo (incl. Junior-, Mini-, Micro MAX
evo) is described. Some overlapping maintenance instructions are treated as generally
valid information at the beginning of this section.
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GENERAL NOTE
Safety notice
mWARNING
Non-compliance can result in serious injuries or death!
Besides our instructions in the documentation supplied, also respect the generally valid
safety and accident preventive directives and legal regulations.
Procedures and
limits
The procedures and limits in this Manual constitute the manufacturers official recommen-
dation for engine maintenance and operation
Instruction The guidelines given in the Repair Manual are useful and necessary supplements to train-
ing. They, however, cannot substitute competent theoretical and practical personal
instruction.
Modifications Non-authorized modifications as well as the use of components and auxiliary components
not corresponding to the installation instructions exclude any liability of the engine
manufacturer
Parts and
accessories
We particularly emphasize that parts and accessories not supplied as genuine BRP-Rotax
parts are not verified for suitability by BRP-Rotax and thus are not authorized for use. In-
stallation and/or use of such products may possibly change or negatively influence the
constructive characteristics of the engine. For damages resulting from use of non-genuine
parts and accessories manufacturer refuses any liability
Special tools Maintenance of engines and systems requires special knowledge and special tools. Use
only the special tools recommended by BRP-Rotax when disassembling and assembling
the engine.
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AUTHORIZED PERSONNEL
General note It is a requirement that all organizations or individuals have the required special tooling
available and the necessary, training or experience to perform all tasks outlined.
Type-specific
training
Any task outlined herein may be performed if the organization or individual has met the fol-
lowing conditions:
Requisite knowledge
• Experience in performing the task and knowledge of ROTAX® Installation/Operators
Manual and Repair Manual
Including:
• Suitable work environment to prevent contamination or damage to engine parts or
modules.
• Appropriate tools and fixtures as outlined in the ROTAX® Repair Manual.
• Reasonable maintenance practices are utilized.
Information Maintenance organizations and individuals are encouraged to contact BRP-Rotax through
its worldwide distribution network for information and guidance on any of the tasks out-
lined herein.
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PROCESS ADVICE
Safety note
mWARNING
Non-compliance can result in serious injuries or death!
When carrying out maintenance and service work, respect without fail the safety
regulations.
Ignition “OFF”
mWARNING
Non-compliance can result in serious injuries or death!
This precautionary measure serves to avoid any injuries in case of an unintentional start
of the engine. Principally ensure the following at each maintenance event:1.) Ignition
“OFF“ and system grounded, 2) Disconnect battery and secure engine against uninten-
tional operation.
Handling of fluids
mWARNING
Non-compliance can result in serious injuries or death!
Non-compliance with this instruction may cause severe burns or scalding! Hot engine
parts! Always allow the engine to cool down to ambient temperature before starting
work.
At maintenance of cooling-, lubricating and fuel system take care without that no contami-
nation, metal chips, foreign material and/or dirt enters the system.
Disassembly At disassembly of the engine, mark the components as necessary to avoid any mix-up.
Take care of these marks, do not ruin them.
Tool
ATTENTION
Avoid mechanical damages.
Never loosen or tighten screws and nuts with pliers but only with the specified tools.
Safety wiring
ATTENTION
If during diassembling/reassembling the removal of a safety item (e.g. safety wiring,
self-locking fastener, etc.) should be necessary, it must be always replaced by a new
one.
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Cleaning of parts
ATTENTION
Use suitable agents and materials.
All metal and synthetic parts are generally washed with suitable cleaning agents. Be-
fore using new and unknown cleaning agents check the compatibility of materials.
Removed parts Before re-using disassembled parts, clean, check and refit them as per instructions.
Use clean screws and nuts only and inspect face of nuts and thread for damage. Check
the contact faces and threads for damages. In case of doubt, use new screws and nuts
Measurements When making low tolerance measurements (s<0.1 mm) and in measuring bearing and
housing components, the temperature of the components and their surroundings must be
in the range 20 °C - 25 °C (68 °F – 77 °F). Only used certified measuring tools!
Nuts Once loosened, always replace self-securing nuts!
Sealing rings, O-
rings
At reassembly of the engine, replace all sealing rings, gaskets, securing elements, O-rings
and oil seals.
Re-assembly Before re-assembly check components whether parts are missing. Only use adhesives,
lubricants, cleaning agents and solvents indicated in the maintenance instructions. If not
respected, damage may be the consequence and no warranty claim.
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CONSUMABLE MATERIALS
General note
ATTENTION
Use only the specified or technically equivalent materials from BRP-Rotax for all
maintenance work.
When handling chemicals, comply with all the customary regulations and specifications
of the producer, including the expiry date and instruction.
NOTE
If necessary contact the manufacturer concerning the comparability of the con-
sumable materials. In some cases information can be obtained from the local au-
thorized distributors and service partners for ROTAX engines.
NOTE
Respect the manufacturers instruction concerning the curing time and the expire
date of the particular surface sealing compound.
The materials specified have been tested for a long time and are suitable for all operating
conditions indicated by the manufacturer.
No. Part no. Description, Application Qty.
1 897651 LOCTITE 243 blue,
medium-duty screw securing agent
10 ml (0.003 US gal.)
2 899788 LOCTITE 648 geen,
high strength screw securing agent
5 ml (0.001 US gal.)
3 297434 LOCTITE Anti-Seize 15378,
for the prevention of fretting corrosion
50 g (0.11 lb)
4 897330 Lithium-based grease or Dow
Corning
to prevent leakage current
250 g (0.55 lb)
525473 XPS Kart TEC Kart Gear oil
Lubricant
1000 ml (0.26 US
gal)
6 898364 Klueber Isoflex Topas Nb52
Lubricating grease
400 g (0.88 lb)
7296160 Engine gasket set 1
–n.a. Cleaning agents as required
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ATTENTION
Use only approved cleaning agents (e.g. kerosine, varsol, etc.) for cleaning all
metal parts.
Do not use lye-based cold cleaner or degreasing agents. Do not clean coolant or oil ho-
ses with aggressive solutions. Clean off sealing compound residue with sealant remov-
er. Soak combustion chamber, piston and cylinder head with cleaning agent and
remove combustion residues with a bronze brush. Very good results have been
achieved with “Clenvex 2000“. It is a solvent-cold cleaner, free of halogen, on the basis
of selected fuel fractions with tensides and is biologically disposable. Never use caustic
or corrosive cleaning.
Figure 2.1
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REPAIR MANUAL
SPECIAL TOOLS
Figure 2.2
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No. Part no. Description
1 277381 Fixation tool for crankshaft
2 276016 Puller assy.
3 676010 Insertion sleeve
4 676021 Insertion jig (oil seal water pump)
5676030 Insertion jig (E-Starter needle bushing)
6 676040 Insertion tool
7676035 Insertion tool (piston pin circlip)
8 877930 Trestle support
9 580132 Tin wire 3 mm 100 GR
10 580130 Tin wire 2 mm 100 GR
11 676205 Fixation tool assy. MAX
12 276051 Crankshaft repair jig
13 276070 Assembly tool bellow spring exhaust v.
14 277364 Fixation, Tool for sprocket
15 676110 Wrench adapter 11/8
16 297041 ROTAX SEAL with bar code
For authorised distributors only.
17 276110 ROTAX SEAL CALLIPER
For authorised distributors only.
18 297240 ENGINE IDENTITY CARD
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