G'Day axy, with the cylinder upgrade to a 50mm piston the oil pump does not supply enough oil, so I will be premixing.
I know that performance 2st engines have higher ratios.
"Most tool, transportation and recreational requirements, such as golf carts, motorcycles, snowmobiles, blowers, chainsaws, tillers, rotary plows, utility tractors, commercial two cycle carts, garden tools, motor scooters, motor skates and other two cycle engines are in the range of 20:1 to 80:1, gas to oil. Many motorcycles are 32:1, others are 40:1 and still others are 50:1. If you are uncertain, consult your owners manual."