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Ok, so, rehashing my project from 2010 that i am just getting to finish. 

according to the other boards seach, i think this is where i left off. scootdawg.proboards.com/thread/35014/edit-identified-carburator-make-jets at that time.  now im back and got/had it running, but now have a weird issue. 

so, i had a what i believe to be a stock carb layin around, so rather than trying to use that filter and rejet the other carb which i failed at, i decided to use the stock carb and i went to the junkyard and got a stock air box (yes, a junk yard here actually buys up crashed scooters, i love it). mostly 50cc but some 150s.  anyways..

motor is a 2005 tank 150 i think, doesnt really matter that much i dont think as long as we know we talking the 150, has a stock airbox, and a stock exhaust.

the carb on it, is standard Kihein style with exposed a/f screw.

so, i got the carb on and the stock airbox, it was running pretty good for about a week, i'd get up to about 45mph or so, i didnt really try to get any more than that so maybe it could have climbed higher?  then, i noticed that it started hesitating one day and within 2 days, i couldnt give it more than maybe 1/4 throttle before bogging down untill i backed off the throttle topping out about a struggling 30mph.  also today i replaced the vacuum lines, the intake mani has 2 outlets, so i ran one to the carb, and one to fuel pump as previous

i pulled and cleaned the carb and put it back together, (NOTE: main jet in there was 103), was messing with it a bit and well, i basically have the opposite problem i had before. NOW... the scooter runs like a champ, until i slow down to a stop and then it dies out i tried it with the stock airbox and with the ebay cone filter thing i had. i am back to stock box,  it seemed the stock box was too restrictive and the cone was obviously too un restrictive.  

The needle in the diaphram is set with the circlip in the top, its one of the needles with 4 positions.  now that im thinking about it, that would be letting the least amount of fuel thru during the upper throttle positions.  the needle was originally set in the 2nd position from the bottom with a spacer on it so it was inevitably in the same space it was in now

since i dont know if this carb was given to me with factory settings or not.. typically...

what position would that needle have its circlip in? 
how many turns out would the A/F needle be?  mine was at 3 full turns out from bottoming out. 
for the idle speed screw, how many turns past making the initial contact would that be set?

also, i seem to have some fuel making its way to the vacuum line at the fuel pump?? i put a clear hose on to see it.  not really sure which way its coming from, i'd guess the intake manifold.

i've searched around an read enough stuff that im a bit confused and frustrated.

is the 103 main jet seemingly good set? 

i'll try to take some better/closer pictures of my setup tomorrow.

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