Ok so I tried a 147.5, 150, 152.5, and a 155 main with no luck. So I just bought a zoom zoom carb and it runs like a top. I put the 42.5 pilot and 150 main in it. How exactly do you do a plug chop? I know it involves cutting the plugs and running at full throttle. Does it matter which gear? and I will do a 1/4 throttle plug chop as well.
The left plug is a new one and the one on the right is a plug I ran for few minutes at about 1/2 throttle.