[Caprimaniac]

Snakebiter; yup- you are correct- I do have a R/L linkage problem as well. It might explain it all. I will look into it today, and hopefully check plugs & all before the weekend.

13; I cannot remember seeing you testing A/F ratio? It's very useful as to get the webers correct. Hesitation at either RPM can be due to too much or too little fuel. It is also possible to trace the problem by reading plugs.

Changing the pump jets (exhaust) to 00 I think is mandatory... See Eljaro's posts on this.