Jetting 101.
How to jet the carb on the YFZ.
Step 1: Drain the carb of gas.
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Step 2: Unplug the TPS and carb switches to spin the carb. Unplugging is optional. You may have enough room to rotate carb without removing the plugs.
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Step 3: Loosen clamps that hold the carb. One on the intake side (not shown) and one on the leaving side of the carb.
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Step 4: Spin carb to access the jets by removing the 17mm nut at the bottom of the carb bowl.
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Step 5: Replace jets as required. In these pics I removed the bottom of the carb to get better pics. YOU DON'T NEED TO DO THIS!
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Step 6: Getting to the needle and clip. Remove the plate on top of the carb.
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Under the plate you'll find an allen head screw that needs to be removed to get to the needle and clip.
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Remove allen head bolt to remove the needle and clip.
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Reach inside the back of the carb to "lift" the needle out.
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Needle and clip.
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WARNING: DO NOT MOVE THE TPS SWITCH WHILE DOING THIS!
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That's my basic "jetting for dummies" tutorial. Make sure everything is clean before doing any of this because dirt is your worst enemy. After you're done make sure everything is put back in place and all switches are plugged in.
EDIT: This is what you'll see on the 06-07 YFZ's when it comes to the fuel screw access. Thanks to Fever2ride for providing the pics.
Yamaha blocked off the access with a plug and you can either pop the plug out by screwing in a sheetmetal screw or take the bowl off and punch it out from the inside.
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[attachment=4730:effects3.gif]
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Step 1: Drain the carb of gas.
Step 2: Unplug the TPS and carb switches to spin the carb. Unplugging is optional. You may have enough room to rotate carb without removing the plugs.
Step 3: Loosen clamps that hold the carb. One on the intake side (not shown) and one on the leaving side of the carb.
Step 4: Spin carb to access the jets by removing the 17mm nut at the bottom of the carb bowl.
Step 5: Replace jets as required. In these pics I removed the bottom of the carb to get better pics. YOU DON'T NEED TO DO THIS!
Step 6: Getting to the needle and clip. Remove the plate on top of the carb.
Under the plate you'll find an allen head screw that needs to be removed to get to the needle and clip.
Remove allen head bolt to remove the needle and clip.
Reach inside the back of the carb to "lift" the needle out.
Needle and clip.
WARNING: DO NOT MOVE THE TPS SWITCH WHILE DOING THIS!
That's my basic "jetting for dummies" tutorial. Make sure everything is clean before doing any of this because dirt is your worst enemy. After you're done make sure everything is put back in place and all switches are plugged in.
EDIT: This is what you'll see on the 06-07 YFZ's when it comes to the fuel screw access. Thanks to Fever2ride for providing the pics.
Yamaha blocked off the access with a plug and you can either pop the plug out by screwing in a sheetmetal screw or take the bowl off and punch it out from the inside.
[attachment=4730:effects3.gif]
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Wow nice post sort of long tho, hahahaha im new here and practically new to my YFZ too, i started with the famous Blaster 
.... well getting back, great post... im having a few backfires after releasing my throttle so ill try to buy a differente needle cuz the one i have only has 1 position or well buy a different Pilot jet
.... well getting back, great post... im having a few backfires after releasing my throttle so ill try to buy a differente needle cuz the one i have only has 1 position or well buy a different Pilot jet
121 - 140 of 159 Posts
