Modern Vespa

How many turns would you give the idle to set it ?

the idle speed or the air/fuel mixture screw?

Speed it's 4 1/2 turns at present

4.5 in or out?

More over, what is the issue you are trying to correct? Too fast or too slow? Did you do anything or did whatever issue just suddenly come on?

I had breakdown out,,, my jets were blocked and my carb was dirty.. so I came to a halt...

They cleaned it for me at the roadside and he said he set the idle 4 and a half turns...

We left it running 10 mins then switched her off then on and took her up and down the road...

Seems to run fine it just sounds a little different to how she was before

Also can smell fuel a bit more if that makes any sense

no, none of that makes sense.

set the idle at 4.5 turns leaves too much room for speculation. 4.5 turns from where

letting it run on for 10min, then off and back on again? odd, unless you were testing for something.

nothing should sound any different unless the work was performed incorrectly- ie something left loose.

anyway, my guess is that something got upset while the roadside work was performed. a fuel line cracked or not fully connected, a saturated air filter due to the bike being down or the air fuel mixture screw being 4.5 turns out would or could give a strong aroma of raw fuel and probably a different sound while running.

if you were out and about, just humming along and she quit on you the chances of you picking up something into the jets is fairly small. my guess is that you've got something else afoot. a bad fuel tap, cracked fuel or vacuum lines, contaminated fuel, possibly an auto choke on its way out.

if it's otherwise running fine, I'd look into finding a fuel leak rather than fiddling about with the carb.

to me, when somebody says they "set the idle at X turns" that means the A/F mix, and if that's 4.5 turns, that's about 2~1.5 turns too many, which would indicate another problem. you don't really set the idle speed at "X amount of turns". that is more of a listen to and feel kind of adjustment.

So it's the one were you have air / fuel
That's the one 4 1/2 turns

Manual states 3 1/2 I think or id seen it on this forum

I thought you needed a special tool to do it when I watched it on vespasport YouTube

I used to use 2 1/2 (A/F) to start with. Then adjust idle speed to get a steady idle. Then tweak the A/F mixture a tiny bit to try to increase the idle speed. Reduce the idle speed to where it was before, rinse and repeat.

Only the US A/F mixture screw has the funny 'D' shaped end - your UK one should just be a normal slotted screw. Apparently the US authorities thought bike owners should be prevented from doing their own maintenance.

Spot on thank you

Do you think with these being out that it's causing the strong smell of fuel ?