this carb is for a 140 cc honda based engine , the same carb (kit) can also be used on slightly larger 150cc lump
he offers jetting for 140 std , 140 tuned 150 std and 150 tuned
as my engine has std head , cam and piston I chose 140 std , however I do have a rather good ex system on the bike , his website makes comments about how larger main jet may be needed when other ex system is fitted , he also includes one size down main jet , to fit "if you are misfiring (running to rich) at high revs"
now to my problem , bike starts , ticks over and acelerates well , but its as flat as a pancake at 3/4 to full throttle , this is on 1 mile duel carrageway run
jet fitted is 112 , smaller spare one is 110 , yup it runs even worse on that !
previous suggestions (via facebook sigh,,,,,,) inc lifting needle , done it , bike runs rich all way to 3/4 then goes flat
jets are easy to get ,
how do i determine when I have reached optimum on jet size , much as " fit smaller jet if you are misfiring" is a tad amature