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Dr 400 carb help

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I have a drz 400 that had a 39 pumper and mrd exhaust already installed with a 3x3 mod.  I took it and a factory xr650l to New Mexico and rode them at 7000 to 8000 ft elevation.  the 650 had no problems but the drz died a lot and just ran bad.  I expected some difference due to the sea level jetting but not that bad.  I started to think that it may be jetted too rich at sea level to begin with.  when idling you can Rev it and it puffs some black smoke., and dies at red lights on long rides.  I've included a picture of the air box mod that was done on it, I've never seen one done like this.  is it ok or does it need a normal 3x3 mod.  the picture of the carb shows how the carb is leaning, I tried to straighten it but the choke hits to fuel valve.  is this a problem,  if so what is the fix?  lastly they removed the oil separater when the smog stuff was removed.  the hose is ran into the air breather box with a filter on the end of it.  the inside of the air box is covered in oil and it dips oil out of the air box after every ride.  is this normal?  I'm going to buy a jd jet kit and rejet  it but just wasn't sure about the rest of these items.

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Turn the idle fuel adjustment screw in a turn or so, should idle better but it sounds like you might be rich every where though. The oil could be from excessive blow by, riding wheelies, or the bike being upside down at some point recently.

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 With the holes in your airbox being drilled on the side, you'll be more prone to drowning the bike in deep water

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I would definetely cover up those holes and do the proper 3x3 mod first.I tried removing the oil bypass breather container-big mistake-you will always have oil going into the air filter housing.That little valve you are talking about comes from the Pair system-i removed mine-not necessary-eliminates the decelerating/popping noises from the exhaust.

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The idle is fine normally riding on dirt and on ride rides where I'm on and off the throttle a lot. It dies (at sea level) when stopping after long constant rpms like on a hwys. How hard is it to remove the air box? I would like to put a new one on instead of trying to patch those holes.

 

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You have a FCR-MX , nice.

The holes in the side really aren't hurting anything, if anything it should help lean it out. It may cause you to need slightly richer jetting than normally recommended.

Without knowing your current jetting, it's a guessing game. If I were to guess, I'm thinking it should be something like 155 main , needle (EMN or EMP) on 2nd or 3rd clip, 45 pilot and 100 paj , 200 maj. Verify float level is at 9mm. A high float richens the jetting across all circuits.

I would put the oil collector box on. There is a lot of debate on the subject, I formed my opinion based on experience with my supermoto.

At 700' I had an issue with the JD needles being too rich down low on my 434. It had a bad case of the sputters at 1/8 throttle. I had to compensate by buying a smaller pilot (40) and running the fuel screw out a bit.



Sent from my XT1650 using ThumperTalk mobile app

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