I've fitted '91 gsxr 750 (38mm)carbs to my '87 gsxr 1100, and having trouble with jet sizes. I bought a factory pro kit, the smallest was a 147.5, and it fouls the plugs after about 2hrs ride time.
The engine is bored to 1127, full stainless micron system & shortened race can and K & N pod filters. Any ideas? Mundy?