Cylinder Kit (145cc) Instruction manual

Product number01-04-0137
01-02-0175 (Piston Kit)

GROM
(JC92-1000001 ～ 1099999)
Adaptation model CT125(JA65-1000001 ～ )Monkey125 (JB03-1000001 ～ )Requirement
Must equipped with our SuperHead 4V+R

Thank you very much for purchasing our products.
Thank you so you will comply with the following matters at the time of use.Before installation, please check your always kit contents.
If there is a point of notice event, Please contact us the dealer of purchase.
This kit (cylinder and piston) exclusively for our “Super Head 4V+R” cylinder head.

CO◎ If the description, such as photos or Illustration different with this part.

☆ Please read carefully before use ☆

◎ This kit exclusively for our“Super Head 4V+R”cylinder head. Cannot be used as parts alone.
◎ During installation, it prepares the tool or the like, do the work with care in accordance with the mounting procedure.
In addition, this manual and genuine service manual are intended for those who have a basic skills and knowledge.
If no experience of mounting, etc., who preparation of such a tool is insufficient, we recommend that it is your request to the shopwith a technical credit.
◎ Export models(other than Japanese model) is not available the compatible FI controllers. Please be forewarned.
◎ This product installation and use, when a problem occurs to after market goods, guarantee other than this product, also can notassume any in any such matters.
◎ If it was the case or mounting that has been processed like a product, it will not be covered under warranty.
◎ It is not possible to inquire of the combination of other manufacturers.
◎ Product may have edges or protrusions. Be sure to wear working gloves.
(Please wear work gloves when working, even if a photo in this article show without work gloves.)◎ Please perform break-in.
◎ This product is generated more heat than stock engine. For long-term high-load riding, we recommend to use SP TAKEGAWA oil cooler
kit and“super oil pump kit”(with relief valve mechanism).
◎ Some of bolts, nuts, dowel pins, and packings will be reused. However, be sure to replace worn-down or severely-damaged ones with new ones.
◎ It may be necessary to change the secondary reduction ratio depending on the weight of the rider and riding conditions.
◎ The sealing washer for the guide roller part is not included. Must be purchased yourself. If the sealing washer is damaged, pleaseuse a new one.
◎ We also recommend installing our“crankshaft support adapter”at the same time.
◎ Recommended parts and necessary parts are listed in the instruction manual (included in the“Super Head 4V+R”kit).

～ feature ～PY○ Uses aluminum with steel sleeve cylinder. Bore 54mm, stroke 63.1mm (same as stock), compression ratio 12.0:1
You can check the cylinder temperature by the compact LED thermometer with M5 sensor(sold separately).
○ The piston rings are designed thin, with TOP: 0.8mm, 2ND: 0.8mm, and Oil: 1.5mm, to minimizing fluttering and friction loss.
○ All piston head are manufactured by CNC machine to minimize individual differences in compression ratio.

CautionWhen the handling of ignoring this display, property damage and human shows the assumption of what injury.

■ This part is a product that was developed for the closed competition, please do not use public roads.
■ When performing the work, etc., be sure during the cold (when the engine and the muffler is cold). (It may cause burns.)■ When performing the work, it should be made to prepare the tools for the job. (Breakage of parts, it may cause injury.)■ The product and the frame, might have edges or protrusions. When working, please wear work gloves to protect your hands.
（It may cause injury.）■ Be sure to each part inspection before operation, check the loosening of the threaded portion, be sure to securely tighten thespecified torque if there is loose. (It may cause detachment of the parts.)

CONTACT Address : 3-5-16 Nishikiorihigashi Tondabayashi Osaka JAPANTEL: +81-721-25-1357 FAX:+81-721-24-5059 e-mail:english@takegawa.co.jp URL http://www.takegawa.co.jp
Please contact with your name and country name provided. (Only English please)2024.9.3

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Warning

When the handling of ignoring this display people died, shows the contents of the serious injury possibility isassumed.

■ The technology and those who no knowledge, please do not to work.
(The cause of parts damage etc., could result in falls and accidents.)■ Always use new pinston pin circlips, gaskets, packings and the like. Worn or damaged ones may cause accidents because of breakage ofthese parts.
■ When performing the work, do the work safely stabilize the vehicle in a horizontal location.
(There is a risk of injury vehicle collapsed while working.)■ When carrying out the inspection and maintenance, etc., if found damaged parts, replace the damaged parts to avoid possible to reuse
the parts. (There is a risk that lead to accidents Continued use.)■ If you start the engine, be sure in a well-ventilated place. In the sealed such place, please do not start the engine.
(There is a risk of carbon monoxide poisoning.)■ During operation, when an abnormality occurs, immediately stop the vehicle in a safe place, please stop running.
(It may lead to an accident.)■ As gasoline is highly flammable, never place it close to fire. Make sure that nothing flammable is near the gasoline.
(It may cause a fire.)■ Inspection, maintenance, the instruction manual or, inspection methods such as service manuals, to protect the way, should be done
correctly.(unsuitable inspection and maintenance, there is a risk that result to an accident.)■ Never use parts other than those specified by us. (Or, the unspecified parts may break, leading to accidents.)■ Do the work must always specified torque using a torque wrench. (Damage of bolts and nuts, and cause of dropout.)■ Always perform repair work should be in a well-ventilated room (caution vaporized gasoline can be dangerous).
（Also may lead to an explosion.）■ Be sure to always use premium unleaded petrol. (Otherwise, troubles such as knocking of an engine may cause accidents.)

CO◎ Please note. Performance up, the design change, the product and the price in the cost up, etc. are subject to change without notice.
◎ Please be informed that we shall be held harmless against any claim against us whatsoever arising out of use of the products inracing and the like.
◎ Keep this manual stored until this product is discarded.

PY

Product content①②

AB④⑤⑧⑥⑦③

NumberProduct content
Quantity
Item Number
1
Cylinder, 54mm101-01-0123
2Piston, 54mm
100-01-0491
3
Piston ring set, 54mm
101-15-015
4Piston pin, 12mm
100-01-0477 (with ⑤ circlip)
5
Piston pin circlip, 12mm
200-01-0478 (6 pcs)
6
Cylinder head gasket
100-01-0479
7
Cylinder gasket
100-01-0480
8L. crankcase cover gasket
100-02-0498

Symbol Product content Item Number
A
Piston Kit
01-02-0175
BGasket Set
01-13-0128※ Please order in the repair parts are always repair part number.
If it is not the part number order, you may not be able to order. Please be forewarned.
It should be noted, In the case of parts that can not be separately shipment, please order a set part number.
※ Repair parts may differ slightly from the kit contents in terms of shape, etc. There is no problem to use it. Please be forewarned.

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■ Mounting procedure※ Please refer to the Genuine Service Manual for detailed mounting methods and specified torques that are notspecifically described.

□ Depending on the condition of the crankshaft (and other parts), it may be necessary to disassemble the crankcase, andtake measurements. To do such are work refer to the genuine service manual and perform the work. If this is difficult towork at your home, please contact with performance shop or TAKEGAWA Factory Mechanic Service.
□ Park the motorcycle in a horizontal place with a maintenance stand, etc□ When installing the FI controller, carefully read the installation manual.

■ Disassemble● Removal of exterior parts○ If necessary, remove the exterior partsand drive sprocket cover referring to theservice manual.
L. Disconnect the harness from thecrankcase cover.

○ Remove the two bolts and remove thecylinder head L. side cover/O-ring, intake
side, and exhaust side hole cap/O-ring.
※ Prepare the pan for oil to drip.

○ Turn the crankshaft counterclockwise andalign the“〇”mark on the cam sprocketwith the protrusion on the cylinder head.

Protrusion
Hole capO-ringCOTorque:10N・m(1.0kgf・m)● Exhaust muffler(stock)removal○ Refer to the service manual and remove
the exhaust muffler.
※ If the exhaust muffler already changed,
remove it following to their instruction
manual.

○ Fix the cam sprocket with a universal
holder, remove the cam sprocket bolt/
washer, and remove the cam sprocket.

Hole cap● Removal of air cleaner case,O-ring

inlet pipe / throttle body

Cylinder headL. side cover○ For GROM, refer to the service manualand remove the air cleaner case,inlet
pipe / throttle body.

● Disconnect all sensor○ Refer to the service manual anddisconnect the O2 sensor and EOT sensor.

● Removal of Cylinder head,Cylinderand Piston○ Remove the spark plug cap and spark plug.

○ Remove the tensioner rod oil filler bolt.

PY○ Loosen and remove the bolts diagonally inseveral steps. Remove the crankcase cover.
※ The L. crankcase cover is pulled in bymagnetic force, so be careful not to getyour fingers penched.
○ Remove the two dowel pins and clean off
the gasket remaining on the crankcase andL. crankcase cover mounting surface.

Oil filler bolt

○ Loosen the cylinder guide roller bolt.
Remove the two side bolts of the cylinder
head.
Guide roller bolt

Side bolt

Dowel pin

L.crankcase cover asket○ Prepare the pan, remove the drain bolt/
sealing washer,filler cap, and drain theengine oil.

L.crankcase cover○ Loosen the 4 cylinder head nuts diagonally(in several steps) and remove (with the4 washers).
Remove the cylinder head.

Drain bolt/sealing washer

Nut / Washer

Torque:10N・m(1.0kgf・m)

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■ Mounting procedure※ Please refer to the Genuine Service Manual for detailed mounting methods and specified torques that are notspecifically described.

○ Remove the cylinder head gasket and2 dowel pins. Remove the slider.
Dowel pinSlider

Head gasket● Installation of Piston and Cylinder○ Install each piston ring ③ .(blow thepiston ring groove with air to clean)※ Install the TOP ring and 2ND ring withthe mark facing up.
※ Do not damage the piston/piston rings.
※ After installation, check that the ringrotates smoothly.
※ Install the ring openings at 120 degreeintervals as shown in the diagram.
※ Install the expander and then the siderails.

CO○ Remove the guide roller bolt / sealing
washer from the cylinder and take out theguide roller.

○ Apply engine oil to the small end of theconnecting rod and the piston pin hole,apply molybdenum solution to the④ piston pin, and turn the piston pin
with the“IN”mark on the piston headfacing the intake side.

MarkTop ringMark

Guide roller

120°
120°

120°

Second ring

Guide roller bolt / Sealing washer○ Remove the cylinder.
※ cover the crankcase opening with a rag,etc. to prevent parts from entering thecrankcase.
○ Remove one side of the piston pin circlip,
remove the piston pin and the piston.

Side
rail

Expander

PY
25mm

25mm

In the directionof piston pin

Perpendicular tothe piston pin‟ IN”mark○ Remove the cylinder gasket and 2 dowel pins.
The cylinder gasket must be removed clearly.
Cylinder gasket

Top ring(silver side)
Second ring

PistonSide rail

Dowel pin

ExpanderPay attention to the crosssection as well

● Check for cylinder interference※ Due to individual differences in crankcases,
there may be interference between thecylinder's crankcase insertion part(sleeve skirt and the crankcase).
never use the engine with interference(may cause engine trouble).
○ Attach the cylinder to the crankcase using
two dowel pins and check for interference
between the cylinder sleeve skirt and thecrankcase.
2024.9.3○ Install the ⑤ piston pin circlip into thegroove of the piston pin hole on one side.
※ Install the piston pin circlip so that it
faces upward/downward, avoiding the notch.
⑤ Piston pin circlip⑤ Piston pin circlip

Piston pin circlip
end-gap

Notch in the piston hole

Piston pin circlip
end-gap

Notch in the piston hole

01-04-0137,01-02-0175○ Install the ⑤ piston pin circlip intothe groove※ Install the piston pin circlip so that
it faces upward/downward, avoiding thenotch.

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■ Mounting procedure※ Please refer to the Genuine Service Manual for detailed mounting methods and specified torques that are notspecifically described.

○ Clean the cylinder mounting surface ofthe crankcase and remove the rag that wasstuck in the crankcase opening.
○ Install the two dowel pins and ⑦ cylinder
gasket to the crankcase.
⑦ Cylinder gasket● Installation of Cylinder head
○ Set the slider on the cylinder andcrankcase. Clean the mating surfaces of
the cylinder and cylinder head. Attach thedowel pin and ⑥ cylinder head gasket tothe cylinder.

Dowel pin

Dowel pin

COSlider○ Apply engine oil to the piston ring andlet it blend in.Apply engine oil after
cleaning the inner circumference of thecylinder.
Install the cylinder with the cam chain
through the cylinder and compressing thepiston ring with fingers.

⑥ Cylinder headgasket○ From here on, please assemble the cylinder
head following to the“Super Head 4V+R”
installation manual.

○ Align the guide roller with the cylinder
mounting hole and temporarily tighten theguide roller bolt/new sealing washer.
Guide roller

PY

guide roller bolt / sealing washer◎ You can see this instruction manual on our website as PDF data .
If this document hard to read, please download it from our website.
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COPY

INSPECTION / SERVICE LIMITS※ This inspection manual is checking and referring to the usage limit of each part (when required for overhaul).
When its new, there is no need to inspect each parts.

Caution : Be sure to use a torque wrench to ensure the torque is maintained.
Warning : Do not perform the work without experience, skills or knowledge.
○ Inspection of Cylinder○ Inspection of Piston Ring
・Check the inside of cylinder for wear and damage.
・Press down a piston ring into the piston with the piston head,・Measure the internal diameters of the cylinder bore at 6 positions;and measure the clearance of the ring-end gap at the horizontal
at the piston pin angle and at the right angle to it (X-Y) eachposition with a thickness gauge.
at upper, middle and lower parts of the cylinder bore.
∴ TOP : If larger than 0.50mm, replace them.
Treat the largest value as its internal diameter.
∴ 2ND : If larger than 0.60mm, replace them.
∴ OIL,Side rail : If larger than 0.90mm, replace it.
∴ Cylinder : If larger than 54.125mm, replace it.
・Calculate the clearance between a cylinder and a piston.
∴ Clearance : 0.12 or more replace
INUpperYEX

COX

MiddlePiston ringLower○ Inspect the crankshaft
When crankshaft is damaged (or has been used for a considerable
amount of time), we recommend inspect the crankshaft.
☆ In case the cylinder wall is beyound the service limits,change the cylinder and piston at the same time as a set. ☆ Complete overhaul are required for inspection.
・Measure the internal diameter at the small end of the connecting rod.
・Check the top surface of the cylinder for scratches and damages.
∴ If larger than 12.038mm, replace them.
・Check the cylinder top surface for distortion with a straight・Measure side clearance.
edge and thickness gauge.
∴ If larger than 0.6mm, replace them.
∴ Usage Limit：0.05mm or more replace
Straight edge

Thickness gauge

PYCylinder gauge

・Check the looseness at the big end of the connecting rod.
∴ If larger than 0.05mm, replace them.

○ Inspection of Piston
・Clear the piston of the remaining carbon residue.
・Fit a piston ring into the piston, and measure the clearance
between the piston ring and ring groove with a thickness gauge.
∴ TOP : If larger than 0.09mm, replace it.
2ND : If larger than 0.09mm, replace it.
Piston ring
Push inPiston

Thickness gauge

・Check the piston for damages.
・Measure the external diameter of the piston at the specified placeat the bottom edge of the piston skirt at the right angle to thepiston holes.
Micrometer890°

・Check the crankshaft runout.
※ For Monkey125/GROM∴ Right : Replace or repair 0.1mm or more
Left : Replace or repair 0.05mm or more

Measurepoint∴ Piston : If smaller than φ 53.9mm, replace it.
・Figure out the clearance between cylinder and piston.
∴ Clearance : 0.09 or more replace
・Measure the external diameter of the piston pin.
∴ If it is below 11.98mm, replace the piston pin.

45mm

74.5mm※ For Monkey125/GROM

Inportant：Please do the running-in enough. If you do not do the enoughrunning-in, it might cause to burning piston, or piston will
shrink terribly and the knocking sound of piston will bigger.
Micrometer
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01-04-0137,01-02-0175〔Ref.〕Running-in
Up to 5000rpm / approx.150km

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