I had just bought this and cleaned the carb and disconnected the brake switch, it starts right up and idles fine, revs up fine in neutral, when driving this thing has no power, i've taken it apart several times and cleaned, the only thing I see that could be the problem is the flatslide with the needle doesn't move, i know it is vacuum operated but can't find vacuum leaks, thanks in advance for any help.

 

I will tell you exactly what it is, its the diaphram, the rubber bowl that sits on top of the slide, Its over a 100 bucks for that piece. I used a gas resistant glue to seal the base of it and hasnt failed me yet. My bike doesnt run 100% but close to it which is fine for now until I can justify paying $100 for a piece of rubber. Hope this helps.

 

thx!!! I resealed it and can now feel a huge difference, now i'm hitting the trails, happy riding!!!