My poor little nc30 isn't running properly

[wacker315]

Hi all. When i come to start my bike when its cold it starts no problem at all with full choke and no throttle. However when i eventually get the choke fully closed the bike dies on me after it judders like its been starved from fuel or something? It will eventually run though after about 10 minutes revving the bike with the choke closed. I have just changed the spark plugs so i am maybe thinking i havent quite put one of the front red leads back over the plug properly? Or maybe something is wrong with the vacuum pipe? Any ideas would be appreciated. cheers all

Sean

[MexicanGringo]

Check the vacuum valve at the petrol outlet from the tank by attaching a tube in place of the one that come from cyl3, if petrol flows when you suck its fine, but if the bike starts & runs fine with choke it is getting fuel.. Check the colour of your plugs, if its dying with no choke, and it is a lack of fuel it will show as the plugs will be light brown in colour, tho you have to idle it/run it for long enough for this to happen which sounds like a problem.. If one plug lead is slightly off the bike wont spin up quickly at all and will be sluggish, so if you rev & you dont get a nice sharp rev it prob is firing on 3cyls, chek the leads & if you want to chek to plugs take them out & touch the plug screw against the frame while turning the engine over, you should see a spark. You might have to take the carbs off and clean the jets&air passage ways out, its not a diffucult procedure