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Discussion Starter #1
1999 polaris xcr 440 sp-I recently cleaned the carbs Mikuni TMX34s. The pilot jets were plugged pretty bad. Prior to this discovery, I cleaned the carbs and didn't take out the pilot-stupid me. So adjustments were made to the idle screw and the air screw. According to the service manual-the idle screw is to be turned out 1.5, and the air screw 1.25. Does this mean that I turn the throttle screw in all the way and back it out till its 1.5 turns out? Or 1.5 turns out from touching the slide? The sled now will not start-like the choke is off??? Prior to cleaning the pilot jets it started but of course I could not get it to idle properly. I think I just need to make some minor adjustments to the throttle cable and slide height. Any advice would be very appreciated-You guys rock!
 

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You got it...From a lightly seat position.
 

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Tighten the screw and then back it out 1.5 turns. Just tighten until snug before backing it off.
 

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Set your air screws from seated all the way in. just to be clear, 1 turn is 360deg not one twist of the hand. Seen that confusion before. Set your idle by the tach. After the sled is warm, open the choke half for a couple secs to get it to idle down form high idle. Then set the tach to 1500-1700 rpm by adjusting your throttle screw
 

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Discussion Starter #5
Thanks! But there is still some confusion-When I tighten the idle screw, the slide actually moves up-far beyond the spec'd .047' gap. Is there an order to this that can help maintain the slide gap and still have a 1.5 turnout on the idle screw?[?]
 

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Discussion Starter #6
Originally posted by bri440pol
[br]Thanks! But there is still some confusion-When I tighten the idle screw, the slide actually moves up-far beyond the spec'd .047' gap. Is there an order to this that can help maintain the slide gap and still have a 1.5 turnout on the idle screw?[?]
Here's what I have figured out-there is no set turnout for the idle screw. When adjusting the slide, you must first unscrew the idle screw out far enough to allow the slide to come down to the spec'd heighth (.047') Can anyone confirn this setting? It seems that when it is adjusted that low, the sled won't idle-even after turning the idle screws in? In retrospect I should have marked the settings for the idle screw/air screw/and slide height (hinesite 20/20). So I can now get the sled to start first or second pull but the idle is still way low like 1200 rpm. I'm looking for some exact steps to "dial" the carbs in so they are operating at max performance and I am looking for a 2000-2400 RPM idle. Can you help me-I've reached a point where I am tired of taking the carbs out and tweaking them to no avail. How about that 12ft snow fall in Redfield:) Thanks guys:)
 
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