Ciao only runs at high RPMs

I have a 1976 piaggio ciao and it will only run when I give it the throttle while I am peddling as fast as I can. It has new points, condenser, HT coil, and a new spark plug. I have re-adjusted the points but perhaps they are the problem still? Should I re-adjust them or something else? Any pointers would help.

Re: Ciao only runs at high RPMs

How high do the rpms need to be? Will it stay running with the throttle open just a little? If so, your idle circuit is probably clogged.

Re: Ciao only runs at high RPMs

What is the idle circuit? I've never seen any on the diagrams.

Update

I discovered by accident that there were sparks coming out from where the HT coil makes contact with the bike. I made my own "adapter plate" because the coil was the old style. here's the video

(edited)

Re: Ciao only runs at high RPMs

If you're using the stock Vespa carb, it looks like this

Re: Ciao only runs at high RPMs

Ok thanks, I'll check that and post what I find. But what about the sparks???

Re: Ciao only runs at high RPMs

Ground the coil to the chassis with more than one bolt. Make sure it has a good contact with the frame.

Re: Ciao only runs at high RPMs

Ok I'll try that next.

Re: Ciao only runs at high RPMs

I cleaned it and confirmed that there is good flow but it still won't work :|

Re: Ciao only runs at high RPMs

when I do that it won't start at all. Could the new coil be bad? There is a small dent that goes across about 3 to 4 layers.

Re: Ciao only runs at high RPMs

I just recently switched to synthetic oil- gas mix, could that prevent it from running? It says in the manual not to use detergent oils.....

Re: Ciao only runs at high RPMs

It will run with synthetic.. What are you mixing it at? 50:1?

Also what did you set your points and plug to?

I believe they call for:

Points: .35 - .45 mm (.013 - .017 Inch)

Plug: .60 mm (.24 Inch)

Re: Ciao only runs at high RPMs

Yeah 50:1 gas mix and both the points and the pug are spaced correctly. My main concern is that I might have ruined the coil. I had it running before the coil was grounded and then after I cut a plate to bolt it on, it stopped working. That's when I found out the coil was sparking where it touched the bolts(ground).

Re: Ciao only runs at high RPMs

change the jet to # 49 or 50

Re: Ciao only runs at high RPMs

I found out recently that my needle and float aren't working properly. I'll just replace the needle and float unless the current 50cc engine run with a 13.13 carb. Does anyone know if it will?

I was thinking maybe this one https://www.treatland.tv/ProductDetails.asp?ProductCode=spaco-SHA-13mm-cable-choke&CartID=1

Re: Ciao only runs at high RPMs

As I said earlier elsewhere I just put the 13.13 carb , dellorto in and my bravo runs way better. As the product description states the choke is too short so I am going to switch it with the original.

Re: Ciao only runs at high RPMs

Thanks a lot! I'll just get the new carb then

Re: Ciao only runs at high RPMs

Exactly. Keep the old carb and study it thats what I am doing. There is a link on the wiki to a dellorto technical manualnwhichnactually explains how these thingsnworknand why and how they can be modified. Itnresidesmon a old tractormwebsitenbut it's in our wiki or forum somewhere. Unfortunately I can't email it to you usingnthisnipad but if you can't find it send me a private email and I will attempt to get you the link. It is a great teaching andnreferencemsource.

Re: Ciao only runs at high RPMs

Re: Ciao only runs at high RPMs

Do u have a relative who is a gasteoenterologist?

Re: Ciao only runs at high RPMs

Yes that's the one!!

Re: Ciao only runs at high RPMs

I don't know what that is, maybe though I have a big family

Re: Ciao only runs at high RPMs

By the way how does the throttle attach? My old one had threads that it screwed into but this one doesn't.

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