Strange running gk76a

[jamestaylor92]

My bike has developed a problem and it only runs properly when you put the power on, if I'm just cruising along at a steady speed (any speed whilst not accelerating) the bike sounds as though it's running on three cylinders, as soon as I open it up even a little bit it runs beautifully. It will not idle, even when I adjust the idle wheel underneath the carbs the idle will speed up for a little while then just die again.
I had the carbs overhauled and balanced mid summer last year and it' ran failtlessly.. I put it away in the garage without riding when it started to turn cold, I'd go and start the bike up occasionally in an attempt to keep it fresh, I've used it to get to work and back since Monday and this problem has been occurring since then.
I'm concerened and kind of hoping that it's the cold weather but I think I'm just looking for the best of a bad situation, any help would be appreciated

[moforockband]

Hi James, that sounds like a blocked idle jet. You will have to strip the carbs to clean it, unless you get lucky and the bit of crap falls out of the jet on its own. To prove SPray water on the bikes headers to find out which carb is the issue. The one that doesn't burn water off instantly is the culprit. The bike must be running on idle for a couple of miuntes at least..

[moforockband]

I didn't have much time to type this morning! It could also be the notorious o rings in your carbs - loads of info on the net and this site. Basically the main offender is the float cradle (perch) by the needle valve, which allows too much fuel into your engine, ruining running and possibly worse. Change every O ring in the carbs if this is the case, if they have gone hard with age.
It could also be a sooted spark plug amongst other things... bad plug lead/ht lead, but check the fuelling 1st!

Hope that hasn't put you off, the gk76a is a great bike, and well worth the effort.
Nick.