Re: 3 questions
Where are you getting those jet sizes? I never use or rely on numbered jet sizes. They have proven to be unreliable. I prefer to use drill size when looking for the best orifice diameter. I'm at about 6000' above sea level here in south Jeffco and I've found that jets that have an orifice of between .025 to .027 seem to give me the best performance.
You must keep in mind that I run my fuel/oil ratio at 100:1 which means I must go leaner on my fuel to air ratio than if using standard 2 stroke oil at 32:1.
If you're not mixing at 100:1 then I would suggest starting at about .028 for a jet size. That will usually require that you use the solder and drill method of determining the jet orifice size. The alternative is to buy a set of orifice drill bits and find what jet size you have by comparing it to the drill bit that fits the hole. Those published or advertised jet sizes mean nothing to me. They are nebulous at best.
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