RE: 90LX quitting while opening throttle past 3/4
Bill,
I think Dub and I chased this in email with you. How did you make out ?
But just in summary..... a few things could be happening it could be going rich to quit, or lean to quit. Might be the plug too
If for some reason you turned the low-speed mixture needle from its factory position, that is one cause. That is more of a low/mid speed mixture adjustment but if turned too far from position it will mess up the transition to the point where it is difficult, with any needle setting, to get it to transition to the top end.
Clearly, the other things to check - ensure there are no holes/kinks in the fuel lines. No bits/particles possibly in the fuel system or carb ( I found a tiny piece of silicone in one engine two weeks ago ... drove me nuts till i flushed it out of the spraybar).
A bad glowplug will light, fire and run, but can blow out when it tries to go to full throttle. Worth a quick plug change to eliminate that variable.
Let me know how things are going.
Bob