One problem sorted, another one appears....I have a Piaggio NRG Extreme air cooled..The bike runs fine, but now will not idle...I have tried adjusting (what I assume is the idle speed screw - big brass thing with spring on it) on the side of the carb, but this has no affect on the engine speed..Am I adjusting the mixture screw ??...Is there another (hidden) screw for the idle ??...When started I have to twist the throttle just a little to idle the bike, if I let go of the throttle, the engine dies......

Also...could it be a choke problem..am I right in undertstanding that it is an automatic choke on the carb..?

And finally..any pointers to any on-line service manuals / pictures would be greatly appreciated..

Thanks

Simon, February 2010

can u help me plz i got an NRG 50cc it starts but when it get to 3500 revs it just stat to cut out could u plz tell me wat to do

marcus, September 2011

ah glad to be of assistance sir,its nice to get some feedback from yourself ,thankyou for the thankyou :)

adam bike doctor, February 2010

Once again..a big thank you Adam,adjusted the mixture screw as you described and now idles perfectly (i may have messed the settings up when i dismantled the carb previously to clean it out)..you are a preverbial font of knowledge..a human haynes manual !!...Thank you again.

Simon, February 2010

ok on the carb there are two screws one on the side withtn he knurled knob and spring and the other that is nearer the back of the carb and recseed into a hole the recessed one is the mixture screw.se theis to 2.5 turns out and then try to adjust your idle screw so it ticks over,if you cant get it to tick over then it possible that either the part on the slide is damaged(worn) where the idle screw touchs it or the piston /bore is damaged and there is a lack of compression which is likeley im afraid.does it idle ok when its warm or just badly when its cold as there is a small brass choke jet in the float bowl and if it has been blown out by a high pressure air line then it will be getting much to much fuel on choke.have a look to see if its there.and yes it is auto choke the choke is the black plastic bit on the top of the carb with wires coming out of it and it should get warm if its working after a minute or so.

adam bike doctor, February 2010