Help with removing your Vespa carb and motor
For me removing the carb and motor from a Vespa Grande or Bravo is easy since I have learned the proper technique. It wasn't always the case the first time I tried and I was terrified of breaking something and it seemed that no mater how I twisted or rattled the motor just did not want to drop out. I soon realized that it was necessary to first remove the carb and air box. Below is the motor, carb and airbox assembled on the bench so you can get a better Idea of where the three screws that you need to remove the components are located. It is often hard to see the screw when all this is buried in the sub frame.
The best tool to do this task is a 8mm or 5/16 nut driver
This is a closeup look at the three fasteners, in order, you need to loosen.
1. airbox screw
2. fuel inlet banjo bolt 8mm
3.Carb mount clamp bolt 8mm
Some how I lost the picture of me bringing the unbolted airbox out the top of this Grande. On the Grande the air box and carb will come out of either the top or bottom. On the bravo the will only come out the bottom. Anyhow, the pic above shows me aiming for the banjo bolt from the top
Here is the banjo bolt. Careful you don't let the filter screen and gasket drop out and get lost.
With the banjo out of the way it is a straight shot to access the carb clamp bolt with your nut driver. On a Ciao, there will not be access to the side with a nutdriver, you must use an 8mm open end wrench to turn the bolt from the top.
Next remove or just back off the two throttle plate screws. On this Grande it is a straight easy shot to them both as the frame is not in the way, On the Bravo model you might have to rotate the carb one way then the other to get a shot at them as the bikes frame is in the way.
You can then gently raise up and out, the throttle plate, slide and spring assembly. Shove this mess out the other side between the top of the subframe out of the way and let it dangle.
Often getting the carb to slide off is difficult and you just need to be patient and keep twisting the carb body back and forth. You can help get this moving off using a fat screw driver inserted between the carb clamp and the motor case. Never pry on the carbs bowl
Eventually the carb will pop off and your can lift it out or drop it down and out.
Take this opportunity to disconnect any wires you see coming from the motor.
With the carb stuff out you can switch sides and begin removing the belt and variator.
Start removing the variator by first grabbing the belt and pull it up or down as far as you can. This forces the belt in between the two cheeks of the rear variator where it will be held by spring pressure.
Now with the belt trapped between the cheeks, you have all this belt slack that will help you slide the variator off in one chunk,
I like to use a strap wrench to hold the front variator still while I go at the crank nut with my wrench.
Hmmm, Variator did not slide off as one chunk like I like but no worries. It is not a complicated assembly.
I hate dirt and grease on my bike, so with the belt and stuff off I like to give it a mopping with rubbing alcohol and rags.
Next lets go after the exhaust. It is easy to loosen the 11mm nut that binds the exhaust header clamp. Once loose you can give it a small spread with a flay blade screw driver.
Back out the rear exhaust pipe hangar bolt.
When trying to get the pipe down you can twist the rear if the pipe side to side while pulling the header in a down and back direction.
"Never get rough with the pipe in an up and down motion" This could snap off the cylinders exhaust port nipple that is cast as part of the cylinder and is very fragile.
You could end up with this heartbreak.
This kit will have to be drilled, tapped and threaded for a makeshift repair to save it. It cannot be repaired by welding and still be reliable.
Now you can remove the three motor mount bolts
This next part of the removal is a sort of dance of motions and scraping of metal on metal. Don't worry, your not going to hurt anything. The worst that can happen is you might pinch a wire between the motor case and the inside of the sub frame. Try to direct the wiring so that it lays back towards the intake opening.
As pictured above, bring the motor straight forward till the crank shaft hits the front of the sub opening
Now lower the motor down so the crank is resting at the bottom front corner of the sub, and at the same time rotate it down so that it points in the 7:00 position.
Next twist the motors head towards you keeping the crankshaft tucked in the front lower corner of the sub opening. This is where the scraping is involved, but just keep firmly twisting the motor towards you as the back of the motor scrapes along the inside of the of the sub.
With no effort the motor will clear out of the sub and you can lower to you bench.
When going back it is the reverse motion. Just lead with the crank aiming for the sub opening. Don't be afraid to spread the subframe ends by wedging in your fist and pushing apart with you thumb. Once you clear the bottom edge with those two case bolts your home.
If you have any questions about this tutorial or can suggest an improvement in this method contact me: Cheetahchrome http://www.mopedarmy.com/forums/profile.php?6,26847