Lean - White Spark Plugs - Aftermarket Exhaust

[Lithil]

Today added on mixture screws +0.5 turns. No effect.

 

Thinking two options:

1. valves are out of tolerances or chain is sadly worn

 

2. aftermarket exhaust allows more air to be sucked back in to process, so i need to:

                                           a) give more turns on mixture screw

                                           b) put needles on higher position to allow more fuel flow 

 

 

 

Your thoughts ?