Originally Posted by
jpz_67
It still has a lot of pinch but every time I start the motor up it is pig rich and not making any power. I let the motor warm up, retune the carb until the motor runs good but by the time I run the tank low and come in for a refuel it richens right back up!
I had exactly the same problems with my GRP .21 Tuned. After reading some other forums someone suggested to try a different carburetor which helped him to stop the tuning problems. I used one from my RB S7 and the problems are gone. The engine is running great now en holds it's tune.