Hi there, just rebuild my GTX, all new crank, pistons, carb kit etc. New fuel line, filters clean, plugs new etc. Took for maiden run and above 4K RPM runs beautiful. From Idle if you give it WOT it runs perfect, just at low no wake speeds, 5 knots, 1500 to 4k RPM it runs rough, like I said if you give it gas it goes no problem, just does not seem to like the low constant 1.5K to 4K rpm range. I this quite normal or is there something I could try to make the low range smooth, kinda sounds like misfiring etc. Low Speed screw 1 turn out as per manual. All else standard. Thank you for reading my post.