2001 yz 125 bogging problem

so i have a 2001 yz 125 that was running good until it started bogging really bad. before all of this i rebuilt and jetted the carb, new cylinder and head, new top end. once i noticed it a little bit later i took out the carb and cleaned it out to make sure nothing got into the jets. it was fine but no diffrence. any ideas?

You didn't jet the carb richer did you ?  A re-build motor typically runs richer.  May not be your problem, but it's worth a go.


For reference, I've got a 1997 YZ125 (which I think is basically the same thing). 

1 size leaner main jet, lowered the needle 1 clip, 1 size leaner pilot jet, air screw 1 1/2 turns out.  Bike funs flawless !

I did a rebuild on my 1999 yz125 and found the same bogging problem. I adjusted the air fuel mixture screw and it solved the issue.


Edited by slaketanley

2001 was the first year of the bigger size carb I believe 52mm. Stock jetting was off on mine I had to play with my jets til it was just right

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