Ciao - Cleaned the carb now it won't idle :(

So I recently inspected the float bowl and cleaned the main jet of my carb (as it was running a little weak when cold and lumpy when approaching top speed).

Great success! The main jet now runs perfectly and gives full power and full throttle!

However now it won't idle at all with less than 30-40% throttle :(

Could I have messed up the idle circuit? I tried to adjust the fuel/air/idle screw in both directions but had no success :(

Any ideas?

Re: Ciao - Cleaned the carb now it won't idle :(

Did you disrupt or dislodge the float needle or float pin in the process?

Re: Ciao - Cleaned the carb now it won't idle :(

when u cleaned your main jet, did u use a wire? use the same on your idle hole.using stock air filter? using fuel filter?

Re: Ciao - Cleaned the carb now it won't idle :(

I don't think so but I will check tonight - thanks for answering

Re: Ciao - Cleaned the carb now it won't idle :(

OK will try and use a small wire on the idle intake.

Stock air filter

No inline filter (just the filters on the petcock)

Thanks for answering

Re: Ciao - Cleaned the carb now it won't idle :(

Yeah, like Pat said, poke a wire thru the tiny idle circuit jet hole.

Re: Ciao - Cleaned the carb now it won't idle :(

SOLVED - OK so the carb itself and all the jets and holes were clean already so that wasn't the problem.

It turns out there is a thick-ish plastic shim that sits inside the carburettor as it fits onto the engine. During the process of taking the carb off an on this shim had worked its way halfway out and this left a big gap for air to enter the system.

Anyway i pushed it back in and now it works great, idles great and is ready for another few years of fun

Thanks everyone

Re: Ciao - Cleaned the carb now it won't idle :(

Same problem here.. Thanks for the tips!

Re: Ciao - Cleaned the carb now it won't idle :(

It’s highly recommended to put an o-ring between that shim & the carb body to prevent air leaks.

Re: Ciao - Cleaned the carb now it won't idle :(

Dirty30 Dillon /

> Seth B Wrote:

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

> It’s highly recommended to put an o-ring between that shim & the carb

> body to prevent air leaks.

100% not needed, just make sure your shim is intake and you seat the carb. The airleak comes in through the gap in the clamp mount, which is completely covered if you have the correct shim, undamaged. The oring is useful on carbs where that shim doesn't exist, a la Puch Bing's.

Re: Ciao - Cleaned the carb now it won't idle :(

> Dirty30 Dillon Wrote:

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

> > Seth B Wrote:

>

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

>

> > It’s highly recommended to put an o-ring between that shim & the carb

>

> > body to prevent air leaks.

>

> 100% not needed, just make sure your shim is intake and you seat the

> carb. The airleak comes in through the gap in the clamp mount, which is

> completely covered if you have the correct shim, undamaged. The oring is

> useful on carbs where that shim doesn't exist, a la Puch Bing's.

I’ve Never needed to o-ring a Bing, but I’ve had multiple leaky SHA shims.

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