A G Bell says 0.71 of bore being maximum and to leave 0.5mm between exhaust and transfers,
I've heard a few different numbers quoted, from different sources from motherland tuner friends over Facebook, UK national based tuners, I'm just wanting to see what others have achieved and maybe for how many hours run time on their cylinders, i stuck with a cautious 55% for my bike.
What do people think is the largest, or what is the largest people have widened their holes too, and what sort of space was left between the exhaust and transfer.