Madass – motor swap

Upgrading the Madass 125 engine (to a Lifan FTP150Lma). Words and pics by Jay Janda.

Want to know what is involved with doing an engine upgrade on a Madass125?  Thanks to Jay at, we’ve got a description of the engine installation process. Please note this is nothing to do with CMG and as such any grief that your sloppy mechanicing brings on you is due to you being an idjit, and nothing to do with CMG. Basically use your noggin’ and these notes as a rough guide only. CMG takes no responsibility for pretty well anything.
Okay, shall we proceed?

Step one:  (Recommended before any major work) – Wash your bike.  It’s easier working on a clean bike, and this helps prevent dirt getting into different places when covers are removed.Step two:  Drain engine oil.


Remove the plug wire.

Step three:  Remove 3 x 10mm bolts holding the upper electrical cover.  Remove 3 x Phillips screws holding the battery cover to the electrical cover.  Remove both covers.Step four:  Disconnect the negative battery terminal.  Make sure it cannot come into contact with the positive terminal.Step five:  Remove the spark plug wire and wire clamp with an 8mm socket.Step six:  Remove the ground wires from both sides of the engine with an 8mm socket, and then reinstall the bolts.Step seven:  Remove 2 x 10mm nuts holding the exhaust header pipe to the engine.


And the pipe.

Step eight:  Remove 2x springs holding header pipe to the muffler assembly.Step nine:  Remove the header pipe.Step ten:  Remove the rear brake return spring and pivot bolt.  It is not necessary to completely remove this, you just need to back it out enough to allow you to swing the brake lever out of the way.Step eleven:  Remove the four Allen head bolts under the engine that hold the footpeg bracket on.Step twelve:  Remove the stock clutch cable.


And don’t forget the inlet manifold!

Step thirteen:  Remove the two bolts securing the stock snorkel assembly.Step fourteen:  Loosen the Carb boot clamp with a Phillips head screw driver.  Remove the two 10mm bolts holding the air box and then remove the air box.Step fifteen:  Remove the intake bolt from the Engine.  Remove intake, carb, throttle cables and choke cable – keeping them intact – and swing them out of the way.Step sixteen:  Remove the two 8mm bolts holding the sprocket cover on.  Remove the cover and remove the chain.


The new motor is ready to fit.

Step seventeen:  Remove the lower/rear motor mount bolt.  The engine should now “swing” from the remaining top bolt.Step eighteen:  With a helping set of hands, remove the top motor mount and lower the engine to the ground.Step nineteen:  Disconnect the three pin yellow wire connector and the blue/white wire.Step twenty:  Prepare the new engine and related parts  (it is recommended you keep the new parts together on a clean surface to avoid difficulty in finding a part.)Step twenty-one:  Place the new engine on the ground under the bike.  Connect the 3pin yellow wire connector and the blue/white wire.


With a little help from your friends.

Step twenty-two:  Have a friend help lift the engine into place and install the top motor mount bolt.  The engine should now be “swinging” again from the top mount.Step twenty-three:  Install bottom/rear motor mount.Step twenty-four:  Reinstall the footpeg bracket.  The stock Madass footpegs will bolt right up with the stock hardware.

Step twenty-five: 
Reinstall the rear brake lever and return spring.Step twenty-six:  Remove the 8mm engine case bolts from either side of the engine and install the factory ground wires that you removed from the stock 125cc engine.


Put all the parts in place.

Step twenty-seven:  Reinstall the airbox.Step twenty-eight:  Reinstall the carb and intake onto the engine, and then into the air box.Step twenty-nine:  Reinstall the snorkel assembly.Step thirty:  The new Lifan 150cc engine has no provision for the EGR used on the stock 125.  Simply plug with a hose and an old bolt, clamping the hose onto the free end of the hose to prevent dirt from getting into the hose.Step thirty-two:  Fill the engine with 10w30 conventional motorcycle oil.  Do not use oils for automobiles.  Do not use synthetic motorcycle oil until after you have ridden 500 “easy” kilometres on the bike, as synthetic will delay the break in process.


And bolt everything back together!

Step thirty-three:  The idle speed will need to be adjusted with the new engine.  You will have to adjust the idle speed periodically during the first 250km as the engine wears in.  The stock 125 carb settings should work fairly well with the stock 150, but some riders may want to experiment with different needle settings and getting to suit their particular environment.


  1. Hey, how was the wiring managed as the sachs comes with a single 3 pin connector (all three wires yellow) while the lifan has more wires coming out of it.

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