1980 Vespa Piaggio granda

I recently acquired a 1980 vespa granda, and its extremely hard to start, i have started it twice and it runs for about 2 min then it stops and wont start again, and i have to be pedaling very fast or going down a hill, for anything to happen. any suggestions or advice on where to start

Re: 1980 Vespa Piaggio granda

Grande not Granda.

https://www.mopedarmy.com/wiki/Fred%27s_Guide is always a great place to start.

Stopping after a few minutes sounds like a bad condenser.

The carb probably needs cleaning if you haven't done that already. Also make sure the plug isn't fouled.

Re: 1980 Vespa Piaggio granda

Ok thank you and I fat fingered the grande, and I have cleaned the carburetor already that was the first thing I did.

Re: 1980 Vespa Piaggio granda

No worries, good luck with the bike!

Re: 1980 Vespa Piaggio granda

Hey if the condenser was bad would I not be getting spark? Or just weak spark. I have a decent looking spark.

Re: 1980 Vespa Piaggio granda

Moped Lar (OFMC) /

You’d get sporadic spark or spark until it heats up.

Re: 1980 Vespa Piaggio granda

To start n idle, did u physically clean n locate idle passage on baby sha? Is your choke working? Are you using stock mesh cartridge n airbox? These are all factors that affect startup n idle.

Pictures help and stating setup w as much detail as possible helps.

Re: 1980 Vespa Piaggio granda

> Moped Lar (OFMC) Wrote:

> -------------------------------------------------------

> You’d get sporadic spark or spark until it heats up.

Or , no spark . ;)

Re: 1980 Vespa Piaggio granda

> P D Wrote:

> -------------------------------------------------------

> > Moped Lar (OFMC) Wrote:

>

> > -------------------------------------------------------

>

> > You’d get sporadic spark or spark until it heats up.

>

> Or , no spark . ;)

Depends on the capacitor type. Most condensers are some form of a metal foil or film capacitor. Modern ones are often "self-healing", in that if a short circuit does develop, it will be vaporized and cleared. Old ones used paper dielectrics and heavy foils, which could indeed fail permanently short . Those paper dielectrics were terrible in that they'd absorb water and their insulation resistance would dramatically reduce.

The typical condenser failure with temperature problem is an insulation resistance failure.

Re: 1980 Vespa Piaggio granda

Ok, I got the bike running and running surprisingly well, when I cleaned the carb the float wasn't working right after putting it back together I fixed that, problem 😅, but I was riding it around the neighborhood then when to the gas station had to put it in pedal mode because I ran out of gas on the way but now it doesn't wanna let me start it again like the belt isn't Catching, is this a common problem and what is the fix for it?

Re: 1980 Vespa Piaggio granda

Did you disengage pedal mode? If not, the rear wheel will spin without turning the clutch (and therefore the belt).

Sometimes you have to roll the rear wheel forward or backwards a bit for the transmission to clunk back into place after you change modes.

Re: 1980 Vespa Piaggio granda

Yes i have, it looks like it's trying to grab and turn but doesn't. I did spin the rear wheel forward and back but nothing.

Re: 1980 Vespa Piaggio granda

Will the motor turn over by hand?

Re: 1980 Vespa Piaggio granda

yes it will, the belt is slipping around the variator, I have taken it off is there any good ways to clean it? I'll be getting a new belt soon as well.

Re: 1980 Vespa Piaggio granda

Xlean what, rust grease bird poop?

Your motor slides as well thus tightening belt. There are three bolts hold motor to frame plus one for exhaust bracket, loosen move tighten. May be a stupid plate that needs dremeled or drilled out on rear hole.

Re: 1980 Vespa Piaggio granda

I would say oil/ grease since when I filled it up I over filled it (my bad) and I think the gas oil mix got down on the belt through the cover but it dose have some rust on it so a light sanding with 120 sandpaper might help/fix it?

Re: 1980 Vespa Piaggio granda

Sure clean it all off. Vespas have super low compression thus do not require using the decomp feature but does your decompression valve n lever work?

Re: 1980 Vespa Piaggio granda

yes it dose, well as far as I can tell

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