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CT70 YX140cc Manual Clutch Electric Start Engine

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MSRP: $735.00
Price: $565.00
You Save: $170.00 (23 %)
Item Number: TB593
Manufacturer: Trail Buddy Inc.

140cc Manual Clutch Electric start with a lighting coil engine is assembled and ready to install. This engine will bolt into any Honda CT70 or other models that have similar bolt patterns such as the Z50, TRX70, SL70, CL70, S65, CRF50/ XR50 and many more. However, our expertise and specialty is in the Honda CT70, other models outside of the CT70 (including the Z50) will require custom wiring, fitting and possible fabrication due to the new wiring, carburetor and other mechanical components for the new motor. These are things you will be responsible for, as we have extremely limited experience in swaps outside the CT70. THIS WILL NOT FIT A HONDA ST90 WITHOUT FRAME MODIFICATION.  Stock footpegs will not work.  **You will need our aftermarket footpeg assembly (TB148). There is a lighting coil in this engine.  This is a 12v CDI system so you will need to review your wiring needs for your application. Our engines are specifically made to OEM Honda standard diameter, so there is no special sprocket that is needed for your gearing options.       

Trailbuddy engines have an installed 420 front sprocket not a 428- so no need to worry about modifying or changing the rear sprocket you already have installed.  This will make it easier for you to gear your bike to either top or low end.  You can find the front and rear sprockets under the CT70 section in the subcategory “sprockets”. Our engines are not heavily gusseted by the top engine bolt which allow for a clean and easy mounting experience. You may want to install the motor with new mounting bolts, please see TB128 and TB129B, respectively.

Our engines also have a full wave rectifier which is a more efficient and smoother rectification.  A full wave rectifier is double the half wave because it converts both cycles of AC to DC.  The ripple factor is less in a full wave rectifier, so the waveform is smooth and easy to filter out.

It is highly recommended that you purchase this fuel switch to work with the carb that comes with our motors: The carb has a single fuel inlet while the gas tank will have a dual outlet. Also, please note that the electric start is on the bottom of the motor so you won't have to worry about reconfiguring where to place the carb/intake and air filter.  

The motor includes:

25mm Molkt Carb, intake manifold, gasket, bolts, spark plug, gear shift lever, kick start lever, 48mm black dual stage air filter, CDI, Ignition coil, 12v Full Wave Rectifier/Voltage Regulator. Bottom electric start.

Engine Type: 4-Stroke,Single cylinder ,Air/Oil Cooler, Horizontal Cylinder Arrangement: Single cylinder  Max Power (kw/rpm): 6.8/7500 Max Torque (N.m/rpm):9.7/5500 Displacement (ml):140CC  Bore x Stroke (mm): 56*57 Starting: Electric/kick start Clutch Type: Multi Plate Oil Bath Type/Manual Clutch Transmission Type:  Gear Shift Pattern: N-1-2-3-4  Front Sprocket: __15__t/420

Connections for the YX motors:
Blue/White wire: Pulse
Yellow: Lights out - Pick One
Green/white: Ground
Black/Red: CDI Voltage from Stator
Yellow : AC out - Pick One

Electric Starter is on the bottom of the motor. Comes standard with a 420 15T Sprocket. All silver in color.  

***Oil is 10w30 or 40 absolutely no more than 800ml from complete drain

**With this engine, if you are purchasing out footpeg assembly (TB148),  spacers will be needed between the motor and the footpeg assembly so that the footpegs will clear the transmission.  This is the only motor that we carry that this is an issue with.  It is a new motor for us and we are working on a better solution for you***


WARNING: Cancer and Reproductive Harm -

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