Quik fuels 750 slayer.
Started surging going down the road, almost died at the stop sign, smoking black, running horrible.
Im going to change out the power valve but also would like to go down in jet size.
Do I go down from 72 to 70 or 68.
Also air idle screws only out 1/4 turn for highest vacuum any more out and it runs bad also.
The web sight says fuel in the middle of the sight glass if I do that it really runs bad and smokes black, but if I put it at the bottom of the glass it straitens out???? whats going on here???

 

Just a trickle out of the sight plugs usually is the rule of thumb. I had a quick fuel 650 double pumper and it ran good with the trickle rule of thumb. As to the surging it could be many things. A seriously lean condition but the smoking black indicates a rich condition. I would check the needle and seat maybe some crud got in there and is making it stick. I had this happen before. My fix was to empty the carb and shake it. it worked but results may vary.

 

Yea, its got the clear sight glass holes and the directions say the middle and it just doesn't work at all.
Also The air idle screws can only be brought out 1/4 of a turn then after that it runs badly and the vacuum take a tumble.
And something I forgot is when I put the air cleaner lid(14X3 brand new reusable) back on it idles down?
Its a recessed base and I think the lid is too close to the front air vent.
I don't know but alot of problems accured all at once and the only thing I noticed is how tight the carb is with its tolerances!

 

After some thought, I know what caused all this.
I cut the rubber fuel line coming out of the tank to the steel line and think some dirt got in the line and made its way the carb.
I thought the carb had built in fuel filters but.......... so anyway Im putting new fuel line and an inline filter, but im still going to change out the jets from 72s to 70s, and and a 3.5 power valve.