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Correct school of thought, engine wear vs. jetting.

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 Given: engine wear reduces carburetor vacuum signal. Whether it be cylinder, vales, or crank seals on a

2-stroke. Reduced vacuum pulls less fuel. So, Ive been thinking about jetting compensation vs. wear.

 I realize that in a perfect world, that one should repair the engine.

 I have been thinking along these lines, please chime in to tell me what is correct. 


1. As the engine draws less air, jetting must be reduced to maintain mixture.


2. As the engine draws less air, throttle opening need be larger. The larger throttle opening reduces 

    vacuum signal at low engine speeds. Pilot jetting will need to be reduced. A/F will be the same at higher





3. Smaller engines like 125mx bikes often carry the same carburetor as 250 2-strokes. They often use larger

    jets than the bigger bikes. Why would the smaller airpump with less vacuum require this?

    Possible ans: Lesser vacuum requires larger holes?


Right about now, I feel like an idiot, and am about to delete this all. What the hell. here goes.

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Theoretically sound....but you leave out a million other factors the wipe this off the map.....specifically, oil intrusion due to wear, heat transfer reduction due to wear, etc etc

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