What's the right gas/oil mixture ratio?

I just bought an 01 cr250 and the local shop recommended me to use amsoil 2 stroke synthetic oil..The bottle says mix it 50:1 but he told me to mix it 32:1. I know a two stroke is suppose to smoke but I guess Im paranoid because I think its smoking a little too much. I could be wrong. Could someone tell me the right ratio?

I burn 4oz of oil per gallon which equals 32:1. I run it in all 2 strokes. Chain saw, weed wacker, cr500.........bonus it smells awesome(benol) I think with today's oils it's not a huge deal as it used to be. Used to ALWAYS CARRY A PLUG with my IT490. My theory is if I'm not fouling plugs in the CR500, then I'm good. That's not a motor I'm holding pinned like a 125 or even a 250. If I was going to see excessive oil buildup, that would be the machine I would go by. BTW in the days- 32:1 was standard. Just run a good premix oil

If you race or ride it hard, mix it at 32:1. If you ride trails and never really rev it out 45 or 50 to 1 would be okay.


Remember, the more oil you mix in, the more it leans the fuel/air mix; meaning pick an oil ratio and stick with it, then correct the carb jetting so the bike runs right and go with that.

Usually excessive smoke is because the bike is jetted too rich, has nothing to do with the oil/gas mix ratio.  I run 32:1 in my 2 strokes and they don't smoke at all once they are warmed up. 


He has an '01 which was factory equipped with the Mikuni TMX carb. They are KNOWN for being pig rich at idle and part throttle.  He can start (wasting time) by attempting to jet it correctly, go to an S7 nozzle, and then constantly fiddle with the air screw every time the temp moves 5 degrees. OR, he can step up to the Keihin 38MM Air Striker carb and begin to love life, and be able to focus on other things.


Can you take a look at the carb and see what name is cast into it?

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