Question about starting jets inside the venturi?

Scorpio1963

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All the info and advice I have been given has been to leave them alone.What I would like to know is if somebody can explain why?What would happen if you decrease or increase thier size?Thank you
 
its because they don't wear and to get them out means destroying them, and possibly the carb body. what's the point?

its like painting your car instead of just washing it!

the issue we face is fitting bigger fuel jets.
 
If you're talking about the pilot air jet:

Replacements are difficult to find or unavailable (I have never seen one yet).

The jet is so large that you can clean "through" it; that is, the jet itself does not inhibit the flow of air or carb cleaner, so there is no reason to remove it.

Theoretically you'd tune the mixture by adding or removing air instead of fuel.
 
its because they don't wear and to get them out means destroying them, and possibly the carb body
Auh mine were easy to get out,I had more of problem removing the pilot jets than anything on my carbs.Im upgrading them 1 size up.
So as far as the starting jets it would have no bennificial purpose to change them because its not going to improve performance of the engine?FTR If anyone destroys theirs I can get them.I happen to have 3 sources where I can buy mukuni carb parts localy.
 
I'm no engineer, but whenever an engine is upgraded for the purposes of making more power, etc, it will tend to move more volume. Since the demands of the engine are greater it makes the most sense to add more fuel. Air is added passively, of course.

If one were to adjust the mixture by removing air a correct ratio might be achievable, but it would not meet the flow demands (for lack of a better term) of the engine.

So basically, the best way to tune is to add something as opposed to removing something. Since air is added passively we will add fuel to keep up with the increased flow and make an ideal mixture.
 
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