I'm pretty much at the end of what I know to do here. I thought I had this fixed but I I haven't had time to do a real ride test. Once it got good & hot and I run the fire out of it, she went right back to the same old crap.
It's a rebuilt motor and the motor is right. Timing and valves have been checked multiple times.
It starts first pull and the motor is STRONG.
It will idle all day long. If you gently roll the throttle it will wind out great. If you mash it wide open too quickly....wuuuuuuhhhh, dies.
It's an aftermarket carb. I have torn it apart, set the floats and replaced the guts with Shindy parts. It has a number 35 needle jet and a 38 slow jet. I have put the needle at all positions with a warm motor. No change. It fouls plugs pretty bad too. Been through three in less than 20 hours. They are covered in black soot so obviously it's WAY too rich.
Only thing I can think of is trying to find a different jet. What number should I try? Any help would be greatly appreciated.