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dr650 / FCR

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So here is where I am at: MJ 138, PJ 48, slow airscrew 9/10 out, here is the wierd part, when I was trying to set the mixture screw I could screw it all the way closed with out the idle changing. So now I am kind of stuck. Thanx, Ed

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Burned, I forgot to mention that turning it out didn't seem to make a difference either?

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ok,lets back up.does your carb have a pilot air screw conversion in place of the pilot air jet under the bell mouth?

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Yes it has the pilot air screw, and it is set at 7/8 out (I double checked)

I took the DR650 out for a flogging tonight after messing with the carb. I have the idle mixture screw at 1.25 turns out now which seems to be the best setting for a strong pull off idle, I am still curious as to why screwing the mixture screw all the way in or out did not ever drop my idle? Any ways it pulls good now off idle and my idle does seem to be more stable when closing the throttle. The other thing I noticed is that around half throttle there seems to be a little wierdness especially if I am at a constant half throttle, kind of a very subtle jerkyness or hicupyness. My pull from half throttle and up is not very strong either, it pulls but it takes a bit for it to build up. I did not do any thing with the main jet or needle yet because I got nervouse about the fact that the carb only has a 138 main. So here are the complete specs:

Needle: ocemr 4th slot shimmed to half way between 4th and 5th

MJ: 138

PJ: 48 (was 58)

Slow air screw: 7/8 out

Mixture screw: 1.25 out

Floats: 9mm

The brass thing that is next to the main jet but opposite the pilot jet is stamped 60, I don't know what this is but I thought it may help. What is this? I cant find it on any diagrams.

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Well it ran good on that evening run, but yesterday morning was a different story. Idle was ok but anything off idle to about 1/4ish throttle was really rough and jerky, I guess I must still be lean down low.

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Not AT idle but it "seems" to help off idle to about 1/4. I have the mixture screw at 1.75 turns, it still hunts (jerky) a bit at constant openings in and around 1/4. I was reluctant to screw out the air jet as I suspect a lean condition already. It had a 58 pilot in it with the mixture at about 2/3 out and the air screw at 1 turn. So to try and get a better mixture setting I went with a 48 pilot, 7/8 air screw and mixture is at 1.75 out now. Problem is the main is only a 138 so I guess I need to get that squared away first?

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EMR needle still?

the straight diameter of that needle is pretty lean.a EMN or EMM will clean up your part throttle jerkiness.

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Ok, I am putting in the JD needle and a 165 MJ tom! While I am in there what should my Main Air jet be? Thanx Burned, Ed

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