How many turns?

[Guest]

Just got my 82 750 e carbs back together. How many turns out is the stock setting on the pilot air screw for the 750? I thought i saw 1 1/2 somewhere?

[tom203]

Stock airbox, exhaust?? start at 2.5 turns

[Steve]

First of all, you don't have a "pilot air screw".

What you do have is an "idle mixture adjustment screw".

The mixture is preset by the pilot air jet and the pilot fuel jet, then the amount of that preset mixture that is admitted to the airstream is controlled by the "idle mixture adjustment screw".

The STOCK setting is usually around 1 1/4 to 1 1/2 turns out, but that was set at the factory to be very lean to meet EPA regulations. The problem is that that setting is too lean for proper running. Most of us have found that opening them up to the range of 2 to 2 1/2 turns works much better.

After going through a set of carbs, I usually set them at 3 full turns out. Then, when the bike is fully warmed up and not using the "choke", slowly turn each screw in, listening for any increase in engine speed. If it happens, it won't be much, so listen carefully. As you continue to turn the screws in, the engine speed will start to drop, due to improper mixture. Stop turning the screw, back it out about 1/8 turn, move to the next screw.

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[Cdnpt1]

Thanks fo the correction, I was going to start with just "that little screw above the front carb hole" ; ) Great advice on some tuning there as well. It is stock and my 450 is running great at 2 1/2 turns so that's where I have this bike as well, but wanted to be sure. On to the second question: did either of you change needle height or is IMA screw adjustment sufficient?

[BigD_83]

Thanks fo the correction, I was going to start with just "that little screw above the front carb hole" ; ) Great advice on some tuning there as well. It is stock and my 450 is running great at 2 1/2 turns so that's where I have this bike as well, but wanted to be sure. On to the second question: did either of you change needle height or is IMA screw adjustment sufficient?

You are not going to know if your needle height needs to be adjusted until you get some riding on the beast under your belt. Hesitation in or rough transitions from pilot to needle to main are going to be your indicators. You shouldn't have to adjust the needle with a stock setup