Gilera runner 125, keeps cutting out

Right gilera runner 125, 2 stroke, when I start it up I have to keep the revs on for it to start then as soon as I let go og the throttle it cuts out straight away,

I have changed the petrol tap and the reeds, do'nt know what else it could be, someone please help, Its got an air filter and is upjetted

 

this happend to me once, turned out that the jet had fallen out and was in the bottem of the carb XD

 

a bit of dirt in your pilot jet, or your idle mixture could be too lean due to the open filter, or the chokes not working...

 

yeah what they said^

 

How would I adjust the idle mixture, and I've checked the jets, and there's no dirt etcand how would I know if the choke is working properly ?

 

Lend a mates choke and try it

 

by capri dave » Mon Aug 02, 2010 9:27 am

remove the choke unit from the carb and connect a 12v battery up to the choke unit terminals, after a few minutes measure if the choke plunger has moved downwards aprox 5mm.

if theres no difference the choke unit is faulty....it's also worth spraying a bit of wd40 in the choke housing, the plungers sometimes stick

 

I think its eaayer to just lend a mates

 

Thanks for that, will give it a try tomorrow

 

the idel screw is a big black one on the side of the carb if ur is the same as mine( i posted my carb on here one ill post link) turn it all the way in the 2 and half turn out or 3 dont matter but that should do it it would run with a choke but will make the bike run rich wont make no diffrence

 

here it is

its about 5 one down

http://scootershack.co.uk/viewtopic.php?f=6&t=19296

 

Thanks for that, I have managed to get it to start without cuting out but when I rev it now its making a noise like somethings rubbing on something, it sounds like when you let a tyre down and you can hear the air coming out it sounds just like that,

 

air leak somewhere or a pipe come adrift somewhere...

would also explain your missing idle

 

that cool mate i had the same problem it was near my rad but after a while it went away but where does the sound come from try and trace it i mean i got a lil tapping noise well i think i do but only when it cold lol