||First start by removing the
farings that are in your way. Sometimes the more the better. On my Mojito,
I only removed the rear faring and the small side farings.
||Next you will need to
disconnect ALL CABLES, WIRES, and HOSES!!! Make sure nothing attached to
the frame is attached to the motor. Don't forget about your brake cable!
||After all the cables, hoses
and wires have been disconnected, unbolt the coil spring at the bottom.
||Once the shock is
disconnected, and you are sure there is absolutely nothing attached to the
motor, remove the main chassis bolt from the swing arm.
||When the bolt is removed, the
scooter will be in two pieces. You may want a second person to hold up the
main frame. Simply lift the frame off the engine and set it aside on
something. You will now be able to install the big bore kit with greater
||You will first have to start
by removing the spark plug, the plastic cover from the cylinder head and
disconnecting the exhaust.
||Next remove the four bolts
located on the top of the head. After the bolts are off gently pull the
head off, followed by the cylinder casing. Remove the gasket at the bottom
of the cylinder, Malossi provides you with a new one to replace it.
||Now you have to remove the
piston. There are ring clips located on each side of the connection pin. I
used a very small screw driver and snapped it out. Then push the pin out
from the other side, being careful not to damage the roller bearing cage.
||Now you have everything
removed, we are ready to install the new kit. This is a comparison of the
old cylinder to the new Malossi kit.
||Here is a comparison of the
50cc piston and cylinder to the new 70cc kit. Notice the difference in
diameter!!! MORE DISPLACEMENT RULES!!!
||The first step is to install
the piston. You will need to put a ring clip on one side of the piston.
The air cooling box to the left of the motor (Looking at it) can get in
your way, so put the pin on the left side of the arrow when the arrow is
pointing at you. That arrow will be installed pointing towards the
Also put the rings on now. Be careful not to stretch them too much, as
they will break in half. Slide the first ring over the top and into the
first groove on the piston. Then step it down to the next groove. Then
install the other ring in the first groove. You will notice a small pin
located inside each groove. These pins should line up where the rings are
||Now we need to attach the
piston to the connecting rod. Place the piston over the connecting rod and
line up the bearing cage with the hole and slide the pin through. After
the pin is in, install the other clip that came with the kit. This is done
easiest with a small pair of needle nose pliers.
||Now we need to put the
cylinder on. Before you put it on, take a small amount of 2-cycle oil and
rub it all over the cylinder walls. This will remove the chance of scoring
the walls on initial start up. Also a small bolt post should have come
with your kit. This is for the exhaust. You will remember that you exhaust
has a bolt and a nut holding it on. Simply screw the short side of the
threads into one of the threaded holes next to the exhaust port on the
Place the cylinder gasket that came with the kit onto the four bolts and
push it all the way down to the motor. Now place the cylinder onto the
four bolt posts with the exhaust port facing down. Slide the cylinder to
the piston until the piston just starts to enter the cylinder up to the
||Make sure that the split in
the rings are lined up with the little pins located in the groves on the
piston. Once the first ring is lined up, squeeze the ring and slide the
head to the second ring. Make sure the split is lined up and squeeze the
second ring and slide the cylinder all the way on.
Insert the o-ring onto the head and place the head onto the cylinder.
||Now replace the four nuts
onto the head and tighten them up pretty snug.
||Now re-install the plastic
cover over the head and re-attach the exhaust. Then put your spark plug