What is the gas-to-oil mixture ratio on a 1997 Suzuki RM 125 Is it safe for me to use a 104 Octane Booster in the bike?

Number 1 you dont need octane booster in a bike. If you want 100+ octane fuel, go buy racing fuel at $5 a gallon. Most fuel suppliers carry racing fuels or can direct you to get them. Now with that said, your fuel to oil ratio will not change based upon the octane of fuel you run, only your timing will change. On a 125 you should be running a mixture of somwhere in the 40:1 range depending on what modifications you have done. Use a good quality oil like Burris synthetic or Red Line and you will good to go with little in the way of carbon buildup on your piston and exhaust. I raced for many years a CR125R and a TM125R Rotary with these oils in the 15k RPM range and they lived a long life only changing out pistons every 3-6 races with little to no gumming of the heads and pistons.