I've has my carb apart about 20 times today. After shiming my needles, the quad would not run above 1/3 throttle. After much troubleshooting I've removed the shims and gone back to stock.

I still have the same problem. Idles and starts great anything above 1/3 throttle and it starts to die out(bog). If I hold it wide open it will not accelerate and will barely run. At zero to 1/3 throttle you'd never know there was a problem. PLEASE HELP....I'm stumped.

 

are you putting the air box back on before test running? i tried running my ac 650 with out the box and had the same prob. the air box must be very restrictive causing it to run lean with out it.

 

when you put your slides back in make sure they can move freely, sometimes the spring binds and causes the slide to hang up

 

Thanks for the replys. Both slides move freely. The weird thing is I can get a little more speed out of it with the airbox off, but its still very poor. I've pulled the main jets and made sure that they didn't get crap in them. I'm completely baffled here guys.

 

Is the Choke Stuck. Is the Belt switch tripped?

 

Bad or Water in the Gas!?! Drain it and see.

 

My first time that I took the airbox off, I put the airbox back with the rubber shield blocking the inlet. It did exactly what you describe.

 

Choke isn't stuck, and the rubber shield isn't blocking the intake. I actually found that the shield was blocking the intake and thought I'd found my problem several teardowns ago...no luck. Belt switch isn't tripped. It doesn't miss or run like a tripped switch either. It goes from normal to a steady blahhh if you push the throttle more than 1/3-1/2. It does act like its not getting enough air, but I can't figure it out. Anyone with a suggestion please chime in.

 

Check the diaghrams in your carbs. All it takes is one little nick to screw them up.

 

I'm thinking it has to be the diaphragms. Hopefully they're not ripped and I've just keep putting them in slightly wrong. Thanks for the help guys.
Just in case, is it possible to buy new diaphragms or do you have to replace the entire slide.