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JUST DID A NEW TOP END ON HER 03 MXZ 380. 145 EACH COLD,130 ISH WARM. ADDED ABOUT A QUART OF INJECTOR OIL TO FULL TANK FOR BREAK IN. HAVE BEEEN BABYING IT SO FAR (45 MILES) SHORT BURSTS OF WOT. IT HAS ALL THE POWER FROM 1/4 TO WOT THAT A 380 SHOULD BUT THE IDLE IS NUTS. THE OIL PUMP IS TURNED UP A HAIR AS WELL(BOUGHT IT THAT WAY. SLED ONLY HAS 250 ON IT. darn MOUSE ATE THE BELT AND BLEW THE MOTOR(LONG STORY) THE IDLE SCREW ARE SET AT ABOUT 3/4 OUT, HAVEN'T TOUCHED THE AIR SCREWS.RAN 35 MILES ON FIRST SET OF PLUGS AND THE DIFF ON NEW ONES, NO CHANGE. IT WILL FLUCTUATE BETWEEN 1500 AND 1750 CONSISITENTLY. IT HAS A STOCK TUNED PIPE ON IT SO YOU CAN REALLY HEAR THE IDLE AND ITS FLUCTUATION. IS THIS A NORMAL TRAIT OF 380'S? OR IS IT THE ADDED OIL TO THE TANK ALONG WITH RICH INJECTION? I EXPECT IT TO IDLE SMOOT LIKE MY 700 BUT W/O REEDS INIT MAYBE THATS IT. CARBS ARE SPOTLESS, NO AIR LEAKS ANYWHERE. NO EXHAUST RESTRICTION EITHER. POSSIBLY CARB SYC? I NEED THE SPEC FOR THIS 03. MY 01 CD I DONOT TRUST TO BE ACCURATE.

-IDLE SPEED (TURNS OUT?)
-AIR SCREW (TURNS OUT)
-ECLIP POSITION
-MAIN JETS #'S
ROUND SLIDE HEIGTH (OUTLET OF CARB) FOR SYNCING PURPOSES

ANY IDES WELL APPRECIATED. MAYBE IT'S NORMAL W/THESE 380'S. NEVER HAD ONE.

I WAS THINKING FUEL DELIVERY PROBLEM BUT IT GETS UP AND GOES GREAT
 

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my wifes 02 idles flat I would guess it could be all the extra oil.I would also use your 01 specs on the carbs at least as a reference point to start with,just use the right model 01.did you turn or take your idle screws out?the ones that raise your slides if you did not your slides I guess would be pretty close.1500 rpm would be a good warm idle speed.check the slide height match to the lower one.if the slides are different that could cause your up and down idle.
 

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When you had the carbs out did you clean them completly. The air screws should be about 1 1/2 turns out. Sync the slides and try backing the air screws out a l/4 turn at a time and see if idle smooths out or rizes. If it rizes lower idle screw and turn air srew in and out to achieve highest idle again, then set the idle. This is a tedius process but realy will make a difference in idle, starting and engagment performance. Good luck
 
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