carb question for fred or someone with a Avanti

Rejetted my carb on my Cosmo when I rebuilt it. went from a #54 to a #58, did some port work on it while it was down. But I screwed up and adjusted the float bowl level. fired up but wouldn't idle, and had to leave the choke on to make it run. adjusted it too far the other way and it wouldn't run at all. had it running for a while now it's dead. the plug is wet. gonna change plugs in the morning (it's a little a fter 3am right now, man were my neighbors PO'd when I fired it up while ago! sounds like a dirt bike after all the work i've done...) think I've flooded her out. Any suggestions?

Re: carb question for fred or someone with a Avant

been messing with the float level. it had gotten moved when I changed the jet. hiriest setting I've seen. when you get it to where it won't have gas flowing out the carb mouth, it won't fill up period. about to say screw it. Any ideas?

carb question - Avanti

I don't know much about Avanti's .. or even what carb they have.

Sounds pretty weird to have the float flow either nothing or too much.

It would seem something is wrong with the float or the needle or seat or something ?

Maybe this is the cause of ALL the weird behavior by your bike.

Re: carb question - Avanti

Matt Wilson /


I've never worked on an avanti, but how are you adjusting the float bowl level.

The only moped that I've seen that you can do this is gurtner carburated mopeds where you can slide the vertically float along the float pin.

Re: carb question - Avanti

Matt Wilson /

Or is it like the bing and dellortos where you move a circlip up or down the needle?

Re: carb question - Avanti

mmmmmm ... much to learn ... matthew ... much to learn

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Most carb's float levels are adjustable by bending the small metal tang that is part of the float armature itself.

And the needle in the canter of the slide on a slide carb has nothing to do with the float or its level.

The float needle and the slide needle are separate an unrelated.

Re: carb question - Avanti

thanx for the input. after a day and a half of messing with the float level on a carb float that looks like something off of a 70's English bike (pretty, but piss poor made), just getting a New carb from Cosmopolitan Motors. already adjusted by some Guy who builds 'em every day. Can promise you, will go out of my way to keep from touching the float on it even when I rejet.

BTW the brand name for the carb on a Avanti/Cosmo is PACCO...deceptively simple looking. uses Dellorto jets, but looks like a Amal or Bing, sort of. When I finally DO upgrade to a 65cc kit, I'll probably get a 15/15 Dellorto or a Mikuni off of a 80cc dirt bike...

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