A 4 stroke will lose power and waste fuel with every little bit of turn too rich on the low speed needle. The key to understanding the low speed needle is that it needs to be just rich enough to take full throttle accelerations and no more. Just right is usually 1/8 turn rich from the point where the engine is too lean.
The big thing most people don't consider is that flying the engine around and listening to it is part of the tuning procedure.
Last edited by blw; 08-22-2016 at 07:46 AM.