So ive been working on this morini project where I modified and designed a 4-petal polini intake on it plus a 19mm carb. Im not sure if I have changed the dynamics of the cylinder with the setup or what. I had a 86 in the 15mm that was on there and now have a 115 in the 19. I had started with a 104 thinking it would be big but had a white plug...fuck. Went and drilled a jet to around a 115ish and it breaks up and bogs 5mph at the top. Tried a 110, hicups a little at the top. Went to a 106 and siezed the fucker. Pulled things apart to check it out, reasonably ok, resealed, back at 115 and I still get a grey plug (this is with it bogging). See pic here:
Now I have gone over the entire topend and exhaust port with 1.5 cans of carb cleaner looking for a leak. Check the stator side seal with cleaner too (which I replaced the crank seals couple months ago), no white smoke so clutch side must be good. Where else can I be leaking?
Could I have altered port timing to the point of this strange behavior with my intake setup? What else am I overlooking. HELP!