Any tool to adjust the air/fuel screw on a 125

Has anyone found/made a tool to adjust the air/fuel screw on a DRZ 125 while the carb is installed and the bike running?

You have to drill out the cover over the mixture screw with a 1/8" drill bit then use something like a drywall screw to pull the plug out. Then you can access the mixture screw.

I understand removing the plug, but there is very little room between the carb, cylinder, and crankcase. I'm wondering if anyone has made/bought a screwdriver small enough to adjust the screw while the carb is mounted on the motor so adjustments can be made with the motor running. That way the air/fuel screw can be adjusted until the motor reaches it's highest rpm, indicating that your air/fuel ratio is correct

The factory mixture screw is on the left hand side, not the bottom. Which carb are you running?

Mikuni VM20. The air/fuel screw is on the bottom, under removed cap, between the carb bowl and cylinder

The only screw on the left side of the carb is the idle screw.

Here's some pics of the carb.. On the left side towards at the bottom is the bowl drain screw.  There is a brass screw above which I assume is the idle/slide stop screw.  Towards the front of the carb in front of the bowl drain screw you can see a forged cylindrical column.  Inside that column is a screw that seams to be the air/fuel screw.  There is also one picture of the right side of the carb.  There is one brass screw to the left of the choke/starter circuit.  Haven't fooled with it yet, but somebody has!



Sorry for the sideways pics

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