Pocket Bike Help!

[xcelerator2]

Ok guys I bought a cheap half fairing 47cc pocket bike with the reed valve. The bike starts and runs good, but when I get it in high rpms it gets distorted a little and then it cuts out , doesn't bog but it like cuts out. I tried a different spark plug and pulled the carb off and pulled the bowl off to peep inside. Appears to be fixed jets, and an idle screw that just controls slide movement for higher or lower idle. I had a full fairing bike that ran great but the steering sucked because of the top fairing and I wanted to get a pipe for the half fairing. I need to get this bike to run right. What do you think the problem could be? Possibility of the crappy fuel filter acting like a main jet at higher RPM? Ignition coil?

Is there a certain source who has the cheapest performance carb and rocket key and boost bottle, pipe? I rebuild dirtbikes alot and mechanical ability is not an issue. Thanks, Shawn

Also do you guys just shave the bottom of the cylinder a thousand of an inch for compression, doesn't that change port timing a little?

Thanks for the help, Shawn

[tblumer]

try adjusting the clip on the needle, if it's in the middle try moving up a notch and see if it helps, if worse move it down a notch below the original setting.

[xcelerator2]

SO pull the top cable/slide assy to acces the clip? All the bigger mikuni carbs on snowmobiles, dirtbikes, etc have the same clip design idea. Will try it, thanks, Shawn