Big Carburetor Kit (PC20) Instruction manual
Product number

03-05-0249 (Carburetor kit)
03-02-051 (Manifold set)

Adaptation model

Monkey / Gorilla (Z50J-1300017 ～ )(AB27-1000001 ～ 1899999)
Monkey BAJA

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

☆ Please read carefully before use ☆
◎ The use ignoring the instructions that are written in the manual, if the accident or damage has occurred, we can not assume any
responsibility for compensation.
◎ 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.
◎ The throttle valve on the motorcycles with frame Nos from 1300017 to 1510400 will not open fully when a stock throttle housing isused. Therefore, it is necessary to either replace the throttle with a high throttle sold separately or process the throttle pipe.
(Refer to a fig. on Page 3.)◎ When a stock throttle housing is used, change from the throttle to the supplied high throttle cables.
◎ In order to install a high-throttle, you need to remove the stock throttle housing. Therefore, you cannot use the front brake lever,turn signals, or a horn switch installed in the motorcycles with a frame No. from Z50J-1300017 to 1510400.
◎ On those vehicles with frame Nos Z50J-1600008 or beyond, you can not use the front brake lever. So you need to prepare a front brakelever and its holder.(A power lever of 06-08-300 is installable).
◎ Please take note that you cannot run your motorcycle in the rain.

CO～ feature ～○ We have designed an easy-to-install carburetor for Monkey and Gorilla for street use, coming with a high throttle cable so a stockthrottle housing can be used. You can easily install this Kit bolt on onto motorcycles but excluding some models, and use aseparately-sold machined funnel, a curling funnel, and an air filter.
CautionWhen the handling of ignoring this display, property damage and human shows the assumption of what injury.

PY■ Work only when the engine and muffler are cool at below 35 degrees Celsius. Otherwise, you will get burned.
■ Always use a torque wrench to screw bolts and nuts tight and securely to the specified torque.
■ As gasoline is highly flammable, never place it close to fire. Make sure that nothing flammable is near the gasoline. Since vaporized
accumulation of gasoline is at the high risk of explosion, work in a well-ventilated place.
■ Always use a hose clip and connect the hose firmly to the carburetor.
■ Never look into the carburetor’s intake pipe carelessly while the engine is running. Flames could spurt by the spitting-back ofgasoline or backfire.
■ The carburetors are shipped out in a factory preset mode. However, depending on the natural phenomena like the weather, temperaturesand barometric pressure, and combination of parts used, the carburetors need re-setting. Rearrange the setting to match each engine.
■ Before driving, always check parts for slack and gasoline leakage. And when something unusual happens to your motorcycle while riding,
immediately stop riding and park it in a safe place to check what has gone wrong with it.
◎ 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.
Product content

Factory Setting of a Carburetor①②⑦③④⑤ ⑥Main jet
Slow jetJet needle
Clip position
Throttle valve
Air screw opening

NumberProduct content
1 Carburetor ASSY.
※ 2 Inlet pipe
※ 3 Inlet pipe gasket※ 4 Carburetor gasket※ 5 Socket cap screw, 6x25
※ 6 Socket cap screw, 6x60
7 Throttle cable COMP.
※ 8 Hex wrench, 5mm⑧#95#3563001
4th.
#20G
1-1/2
Quantity1111
3111※ means the parts are a part of a manifold set.
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)2022.2.7

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

Please check the contents of this kit.

（Preparation）
CAUTION：Make sure that the engine and themuffler are cold enough.
Stabilize the vehicle.

○ Unfasten the pan screws on the throttle
housing and disconnect the throttle cable.
Wipe off soiled or worn-out grease.
※ Be careful not to lose the throttle
housing or pan screws for reuse.

○ Remove the side cover, demount the seat,drain the gasoline in the fuel tank,close the fuel cock, and pull out thefuel hose on the carburetor side.
And then demount the fuel tank.

Pan screw○ Detach the top cover of the PC 20
carburetor, and remove the throttle valve
spring and the throttle valve.
○ Run the throttle cable to the carburetor
in the same way as a stock cable is run.
Fix the carburetor top to the throttle
cable, and install the inner cable tothe throttle valve with the throttle
valve spring compressed.

Warning：Handle the gasoline with thegreatest caution.

CO○ Fix the earth wire to the frame with an
air-cleaner mounting bolt.

○ After making sure that the fuel cock isclosed, open a drain cock on the carburetor,and drain the gasoline from the float
chamber to a tray or something.
Warning：Handle the gasoline with thegreatest caution.

○ Align the notch on the throttle valve inthe direction of the throttle stop screw,
and then install it to the carburetor.

Earth wireNotch○ Keep those removed parts in a bag or thelike.

（Installation）

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CAUTION：Be sure to tighten to the specified
torque with a torque wrench.

Drain cock

○ Fix the supplied throttle cable to theunder throttle housing loosely for now andthe inner cable to the throttle pipe.

○ Unfasten an inlet-pipe clamping bolt andair-cleaner mounting bolt to demount an aircleaner box, and the carburetor with an inlet
pipe attached to it.
※ Be careful not to let any foreign material
fall into the intake port.

Torque：10N・m（1.0kgf・m）

Note: Be sure that you protect specified
torque.
Pan screw

Torque：8N・m（0.8kgf・m）

Pan screw

Top cover2022.2.7○ Place the carburetor gaskets between
carburetor and inlet pipe, and fasten
them together with a 6x25 socket cap
screw, and tighten to the specified torque.
Note: Be sure that you protect specified
torque.
Socket cap screw○ After applying grease to the sliding
surface of the throttle, install thethrottle housing. Then tighten the panscrew.

○ Remove the throttle valve from thecarburetor. Separate the throttle valve
from the throttle cable. And remove thetop cover from the throttle cable.

Throttle stop screw

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

○ Remove the clamp on the wire harness.
Fix the wire harness, sliding it until it
does not interfere with the carburetor.
Install the gaskets and inlet pipe to thecylinder head in this order, and fix themby fastening the 6x25 and 6x60 socket cap
screw to the specified torque.
Note: Be sure that you protect specifiedtorque.
Socket cap screw

Torque：10N・m（1.0kgf・m）○ Pull the choke lever to start the engine,and check each section for intake leak.
Gradually pushing the lever back, warm up
the engine till the revolution becomessmooth. And then push the lever back into
the original location. If the motorcycle
does not run idle, or it runs idle at highrevolution after warming-up, adjust therevolution with the throttle stop screw.
○ Do settings in a safe place according tothe specification of your vehicle withenough care.

COProcessing Throttle Pipe

Clam

Wire harnes

Socket cap screw○ In case a stock housing is used in thevehicles with frame number Z50J-1300017
to 1510400, rasp the shaded part of thethrottle valve as indicated in thefigure below○ As for the vehicles with frame number
Z50J-1600008 or above, there is no needto process as above.
Throttle pipe

○ Adjust the free play at the throttle
grip to be about 5 mm by turning theadjuster of the throttle cable. See thefigure below. Snap the throttle several
times to make sure that the throttle
moves smoothly without sticking and also
to check that the valve is fully open.
※ Also check that the throttle has freeplay even when the steering handle isturned all the way to the right or to theleft.
About 5mm

○ Fix the fuel tank and the seat.
○ Make adjustments of the direction of thefuel cock and the length of the fuel tube,
then insert the fuel tube into the fuelcock and the carburetor, and attach thetube clip onto the fuel tube. Open thefuel cock and check every parts for oil
leak.
(Do not leave the cock open for a longtime.)

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RaspPY
/3How to Set the Carburetor
・When the carburetor does not match the engine and the engine fails, the engine failures are caused by either too dense or too lean
air-fuel mixture.
・The engine failure symptoms for the engine are as follows:

When the air-fuel mixture is too dense:

When the air-fuel mixture is too lean:

・The explosion sound with a dull thud continues
intermittently.
・The engine malfunctions further if you use the choke.
・The engine malfunctions when you warm it up.
・The engine works well if the cleaner is detached.
・The motorcycle belches dense (or, black) exhaust gas.
・The plug smolders, getting blackened.

・The engine overheats somewhat.
・The engine starts working well If you use the choke,.
・The engine does not accelerate well.
(No smooth acceleration)
・Revolutions change, generating weak power.
・The plug burns white.

CO※ Set the carburetor only after warming up the engine, and then test-drive. And use a plug with the right heat value.
※ Do the setting in the following manner, studying at what throttle opening position the engine starts failing.

○ Jet needle (Throttle position at 1/4 - 3/4)
Whether or not the engine revolution is in proportion to the throttle operation
・When the acceleration is not smooth or even, make the air-fuel mixture dense.
・Make the air-fuel mixture lean when the engine revolution goes up heavily and belches black gas.
The mixture ratio at this throttle position can be adjusted by the location of E-ring in the grooves. The air-fuel mixture
becomes dense as the location of the E-ring moves down from the 1st to the 5th groove.

3rd groove
2nd groove
4th groove

1st groove

5th groove○ Main jet (The throttle position at 3/4 - 4/4)

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・The air-fuel mixture ratio at this throttle position can be adjusted by changing the number of the main jet. The larger themain jet numbers, the denser the mixture ratio becomes.
・In view of the engine and muffler specifications, select the most appropriate main jet to get the highest revolutions.

○ Slow jet / Pilot jet (First of all, please adjust the air screw.)・In case you have given more than three turns to the air screw to tighten it, use a slow jet / pilot jet with a small number.
・If you have tighten the air screw (clockwise) to the full, use a slow jet / pilot jet with a larger number.
Check whether you have made a right choice of the pilot jet by seeing if the engine starts up revolving smoothly from theidling to running at slow speed.
・When the engine revolves up unevenly, the slow jet / pilot jet number is too small. (At idle)
・When the motorcycle belches black exhaust gas and produces heavy exhaust sound, the slow jet / pilot jet number is too big. (At idle)
・After replacing the slow jet / pilot jet, you need to readjust the airscrew.

○ Air screw

The air screw adjusts the air mass flow at the time of engine’s revolving at slow speed. (At idling)
・Give the air screw a right turn → The air-fuel mixture gets dense.
・Give the air screw a left turn → The air-fuel mixture gets lean.
Loosen the tightened air screw back to the 1.5-turn position. And then from this position, give to the airscrew a right or left
turn of 1/4 to 1/2 till the engine revolves at the highest speed.
Loosen the idle stop screw till you get the steady idling revolutions. And once again adjust the position of the airscrew to get
the highest revolutions.

● On how the barometric pressure, temperatures and humidity affect the setting:・At highlands or at high altitudes, the barometric pressure and air density go down and the air gets into the carburetor in lessamounts.
This makes the air-fuel mixture dense which was adjusted at low altitudes.
・Under the weather conditions with very low temperatures, the air density increases, which makes the air-fuel mixture lean.
・Under the rainy and humid weather conditions, the air density decreases, which makes the air-fuel mixture dense.

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)2022.2.2