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Shouldn't pilot Jets be larger the higher number on 4 stroke?

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I'm trying to figure out the jetting on my yz250f, it's behaving like its lean on the pilot jet so I bought two sizes larger (42 is stock) a 45 and 48. The problem only got worse larger I went, but I thought it was strange that the fuel channels got smaller the larger the pilot jet got. Shouldn't these get larger to allow more fuel?

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Just now, Krannie McKranface said:

There is no reason to change jetting if the bike ever ran well with the jetting it has.

Most likely you have a leaking hot start or air boot.

It has never run well for me. How can I check if the hot start is leaking? I know I have no air leaks on my intake.

The Hot start doesn't help during hot starting and if I pull it while it's running it doesnt effect rpm or performance...

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You do not describe the problem that you say is jetting. Lean on the pilot would be hanging or high idle.

You made no metion of the fuel screw, which has an oring (and washer) that must be new to seal, and it must be adjusted rpm on a hot motor.

A 'real' fuel screw is advised like the R&D fuel screw.

The hot start is obviously not working, so, it is at leat part of the problem.

http://www.dirtrider.com/features/protips/141_0707_keihin_fcr_carb_rebuild/

 

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I didn't go into too many details on the problem/s as I have another thread that fully explains all the issues. 

I was just curious why the higher numbered pilot jets seemed to have smaller fuel passages, thought they would be the other way around.

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Non-OEM jets can be screwy. OEM jets, yes, the larger the number, the larger the passage way. You may also have jets that someone 'reamed out', thereby making a small jet large.

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