This would depend on what type of oil you will be using for your premix. The oil base stock is either petroleum, semi-synthetic or synthetic oil and is mixed with gas at a ratio ranging from 16:1 (petroleum) to as high as 100:1 (synthetic). I personally ride a 2001 Kawasaki KDX200 that I run Yamalube 2R at 36:1 with no problems. Although synthetics say you can mix them at 100:1 I would not, that seems way too lean to me.
32.1
50:1
You need the mixture of gas and oil mixture for 2004 YZ 125 in the ratio 1:32.
32:1
32 to 1 is the stock ratio. Most modern 2 stroke oils can be mixed leaner.
32:1 for motocross 40:1 for trail riding
Use 40:1 and run a BR9EG spark plug.
32:1 for KX 40:1 for YZ Not sure the ratio on CR's, and RM's.
40 parts gasoline one part two cycle oil
i have a yz 125 and i use 40:1 so 125ml to 1L
The correct fuel to oil ratio for a 1996 Yamaha YZ 80 is 60 to 1. The bikes have a single cylinder, 2-stroke engine.
Consult the manual. Each oil company recommends the ratio for each product. Silkolene can be mixed at any ratio desired. Go to silkolene.com/productchooser.com and go to Yamaha YZ-125 for the proper application. Follow the directions on the bottle. I use 36 parts of fuel to one part of oil. (36:1).