Modern Vespa

Hello! We just got a 1973 Vespa Piaggio Ciao yesterday, and the engine still runs, but it will not stay running. Whenever we pedal to start it, the engine will run, but as soon as we stop pedaling the bike, it will stop running.

Has anybody had any experience with something like this? If so, please chime in!

Paging Dr. Ona...

Correction: It doesn't run at all. We have been mistaking the sound of us cranking it over as 'running' and then stopping when we stop pedalling. We still can't get it to start. We have crazy amounts of spark.

Clean:
The tank
Petcock
Carburetor

Install:
New fuel line
Inline paper filter

Use new pre-mixed fuel. It should run after that. Once it's running check timing and air leaks. Do a plug chop as well just to make sure you didn't miss any air leaks.

So here is what we've determined. When we pedal it, it will OCCASIONALLY blow what looks like exhaust OUT of the head. Could it be a bad head/gasket or is this normal? This dust/gas is accompanied by a brief "hiss" coming from the motor. We know the spark plug is sparking, and we know that the carb is clean because we just cleaned it. Fuel is flowing into the carb because the carb was FULL of fuel when we took it apart, so fuel IS getting there. The engine code on this thing is C7E1T.

Good advice so far...
How's your compression?
Is the decompression lever stuck open?
Points... check them for correct gap... very important for Ciaos/Grandes since you can't move the stator for timing.
Is the exhaust clogged?... take it off and see if you can blow through it.

Do these and check back..

ps...

http://projectmopedmanual.info/Manual_HTML/vespa.html

Is the head on tight?
Don't over tighten the four nuts..
Also, check to make sure your exhaust nuts are tight ( no jokes )

Doc Moped strikes again

Hi. I'm just learning hope to use this forum so please forgive me. I too have a 1973 Vespa Piaggio that needs service. I am in the lower Hudson Valley of New York and am seeking a place to take her. Any advice?

Go lurk Moped Army and good chance you'll find your answers.

I appreciate the reply. Please forgive my ignorance but how do I lurk them. This is all new to me.

Mopedarmy.com

Sign up so you can use the search function, then read threads. Lots of good moped tech over there. If you go into their tech section there is a whole section on Piaggios and Fred's Guide which is a good generic "git this sucka runnin" how to.

Thank You!!