Originally Posted by The Ace Face
The bike currently will not stay running unless the choke is about half way and when I throttle it up it sputters and and bogs down and stalls if I shut the choke off.
I have a feeling its something with the fuel or bad spark plugs.
These type carbs have a "fuel enrichment system" that is different from the traditional butterfly choke plate we all grew up with here in the US. Whereas a "choke" closes off the incoming air to the carb throat to create a rich mixture, the "fuel enrichment system" is a rather large auxillary fuel circuit drawn straight from the float bowl. Both sorta do the same thing but in entirely different ways yet both are commonly referred to as a "choke".
With your bike only running with the 'choke' on, it is being fueled only
by the auxillary fuel circuit which implies that you are getting little to no fuel from your idle circuit. Most often this is the common problem of a clogged pilot jet that supplies your entire idle circuit. Falling with any advance of the throttle may also indicates there is insuffecient fuel supply to the transitional idle bleeds behind the primary/initial idle bleed.
303 has a point about the idle setting in that the throttle plate must
be advanced enough to expose the first of the idle bleed holes. However, from my experience, giving the idle speed adjusting knob 'a couple of turns clockwise'
would be just way too much... but I get his point. Perhaps too much to even start and if so, idle way out of control. As some sort of a reference, a cold summer start on mine without any 'choke' is nothing but a 1/4 turn clockwise to get it to light up with a 1,500rpm cold idle.