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Has anyone here adjusted a ZR440 with round slide carbs.

I am using 330 jets.  The air screws are 3/4 turns out.  (book says 1.25 turns out)  Elevation here is only 300 feet.  The chart on the air box tells me use 330's for -7 to -18c (right in par with our weather)

I am finding that the sled is hard to start and idles funny.  Once warmed up the idle is at 2500rpm, but after idling for 2 or so minutes the idle drops to 1500rpm and sounds like it is operating on one cylinder.  Give it some throttle and the rpm's go up and settle on 2500rpm.  Then same thing happens again.  I have check the choke cables and readjusted so there is plently of slack.

Any ideas?

newf
 

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I have a 97 and it idles at 1700 approx. I had it at 1500 and it was alright. You could crank up your throttle stop screws a half a turn each and then see how it idles.

What size pilot jets do you run? They should be 30-35's. Check that. Also-your main jets could go down to 320's or 310's.
 

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Discussion Starter #3
Pilot jets are factory, I have no idea what they are.  I never check them.

How cold of a temp can I run 310's or 320's?
 

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sick a finger in each carb and make sure the slides riase at the same time even a 1/8 inch off is bad also make sure they go past the top so wide out (is wide out).  my idle drops to i think it's on a lot of rides not a problem though.
 

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zrkenney I think your right on.  Sounds like the same problem that both my zr500 and previous cougar 550 have had.  After I synched the carbs they both have pretty much stopped doing the wierd idle thing.  They both use 38mm round slides.  There should be little sight glasses on the carbs to help you synch them.
 
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