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I was wondering what the stock carb settings are on the big block Polaris 700 motor with the 824 cyls.and kehin 39mm d slides (main
jet, pilot jet, idle screw, air screw, needle etc.) I pulled the carbs off last night to clean them. I pulled all the jets neddle seat etc. and cleaned them along with everything else.

It had a 205 main jet and a 38 pilot. No mods except for a DG can, boost bottle, and heel clickers. I don't really know what they mean when they say what clip it is set at on the needle (can someone explain this.) Also I think I have heard of some upgrades on the needle. Is this true? And also heard something about the pin that holds the floats in the two towers being to small and you can fix it some how.

Which is the idle and air screw? There is a black knob that looks like that it is the idle screw.and the air screw, is it the one that is at the bottom of the carb, kind of set in it. And why are the vent hoses for the carb mounted in the air box? There was also a different motor put in this sled. How can I tell what year it is?

If you know of any mods of setting that I can do to make these carbs not so finnicky i would appreciate it much.

Thanks,
Jake
 

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http://www.snowmobilefanatics.com/forum/topic.asp?TOPIC_ID=9535&SearchTerms=keihin,needle

Do a search for Keihin carbs. There's a bunch of info on this site for you to learn from.

To raise the needle jet you remove the "c" clip and put it on a lower ring on the needle. You need to see a needle to understand. Dropping the needle leans the mix in the 1/4 to 3/4 throttle range of the carb. Raising the needle richens the mix.

The needle you want is a 1371G. You want to turn athe air screw out 1.5 turns from all the way in. you also want to sync the carbs. Do asearch for that too. There's a really easy way to build a sync tool.
 

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MAIN 185/185 I have 182/182 stock pipe
Pilot 38
Needles (stock) 1368G get the 1371G
Black knob is Idle adjustment
Small brass flat head screw is the air screw, Play around with this to get the best throttle response OUT=LEAN IN=RICH.
Get it to idle at 1600RPM if it doesn't want to idle at that then put in #40 Pilot jets.
Vent hoses are attached to air box to create a negative bowl pressure.

You can switch to the Mikuni rack carbs 40mm off I think it was a 2001 700. Just listen to your motor and CHECK YOUR PLUGS AND PISTON WASH play around with different air/screw settings.
 

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This is frickin sweet I just found it:
http://www.carbparts.com/keihin/needles_tuning/jetting_your_carb.htm
the graph is nice
 
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