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DRZ 400 How are you turning the fuel screw?

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I just cleaned the carb on this bone stock drz400 2003, and it starts and runs fine on the choke, but it will die off the choke and the idle knob makes no difference so I know the fuel screw needs some fine tuning. How is it possible to turn this screw with the carb on and bike running? What is the stock setting? I think I set it at 2-1/4

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Tennxr , you need an extended fuel screw to take the pain out of adjusting it , like the one in the FCR below . TT sells that one for $20 , or you can buy one of many other brands , flexjet is popular as it is flexible and looks like the idle adjuster . But you can also cut down and make a small screw driver to use . This will work but is very fiddly and could be hard to use depending on the size of your hands , greg

carbswapout006.jpg

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I do not have time to order one, do you know what I should set it at, I am thinking around 3 turns out. Everything is stock.

Thanks for the reply

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use one of those drill bits that has a flat head on one end and a phillips on the other. it is a pain to use and you will get singed, but it works to get the starting point of 2.5 turns out.

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it starts and runs fine on the choke, but it will die off the choke and the idle knob makes no difference

Unless you have screwed the fuel screw in all the way, I would suggest that you might have a blocked pilot jet.

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I just turned it to 3 and the problem is still there. I would think it was the pilot but it will idle, it just has an extreme bog right off idle. I am going to take it back off and e inspect everthing. Any suggestions greatly apreciated.

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I would think it was the pilot but it will idle, it just has an extreme bog right off idle. .

Have you taken the bike for a ride and got it up to temperature?

Mine will run lean off the bottom and bog until I get it up to temperature, then it runs spot on.

Adjustment of the fuel screw and idle should be done at operating temperature.

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No, you need to get it to full temperature by riding around if it will let you. If you set the carb with a half warm engine you'll find that it won't return to idle once it warms up completely. If you can't wait for a needle you could go out and buy a 90 degree screw driver but it will cost more than the screw. I used one of those to balance the carbs when I had a 4 cylinder bike.

Steve

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I just cleaned the carb on this bone stock drz400 2003, and it starts and runs fine on the choke, but it will die off the choke and the idle knob makes no difference so I know the fuel screw needs some fine tuning. How is it possible to turn this screw with the carb on and bike running? What is the stock setting? I think I set it at 2-1/4

Make sure it's at normal running temp...

Turn the fuel screw in till the idle drops/misses..Then turn it back out until the idle peaks.

This should happen between 1 and 3 turns on the stock mikuni.

If you end up at less than 1 turn you need a smaller pilot jet and more than 3 turns you need a bigger pilot jet...

Try it at 2 3/4 turns as a starting point...

I recommend you install a JD jet kit to get it running correctly...

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I just took it back apart, everything is clean

Pilot jet is a 45

Main 142

Is that the stock Pilot?

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It's the pilot I would have installed a 50 but the dealership only had the 55 , the 45 was way lean so I took a gamble and it worked!

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is it 2.5 turns out from rpm drop or from fully in? don.t want to wind it out too far that it comes loose.

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