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i just synchronize my carbs on my 500 polaris indy SP. I took the plunger and made both even to the top of the hole on the carb that goes to the motor at full throdle. So they were both even i put it all together started it up and its idling at 4000 rpm with the idle screw almost all the way out. Should i make the plunger even with the front of the carb ( the part that goes into the air box) Please give me a few tips.
 

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Wheelman you should sync your carbs with the slides closed. The reason your idle is so high is because the cables are too tight and your slides are not returning all the way. Make sure the idle screws are set equally and then adust the cables so that they both move at the same time. There should be a slight bit of play in the throttle cable. Let me know if you need more detailed directions.
 

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Wheelman,

What I recommend is that the carbs be adjusted to the service manual with the carbs hanging off the side of the sled, then finding something to use as a calibration once the carbs are on the motor, then doing the final adjustments of the carbs while they're on the motor.

For example, my Mikunis in my Formula STX needed to have their idle screws backed out until the slides are totally bottomed out as the first step. Best way to do this is with the carb in your hand and a droplight behind the carb so you can see if any light is shining through the back of the slide. If not, you're bottomed out. If so, you're aren't there, yet. Once bottomed out, the idle screws had to be adjusted back in just until they touched the slides. Again, the droplight behind the carbs really helps to know when this happens as you're turning the screw. Once the screw touches the slide the next step was to screw in exactly 2 full rotations.

Then, this is repeated for the other carb.

THEN, my next recommendation is to find something that you can use as a "Go No-Go" gauge. I used drill bits from a set that increments by 1/64th of an inch, or 0.015625" (which is 15.625 thousands of an inch). I found the one drill bit that would just barely fit under the cutout in the front of the slide after doing the initial 2 screw rotations up from bottomed out, and the very next size bigger WOULDN'T fit. Both carbs were exactly the same at this point. These 2 drill bits just became my calibration points.

Then, put the carbs back on the motor.

Then, test the slides again, using those same 2 drill bits. The smaller one needs to just barely fit. The next size up shouldn't fit, just like when the carbs were not on the motor 2 minutes ago. If it does (like mine did because the cable pulled the slides up when the carbs were put back on the motor) then you need to re-adjust the adjustments at the top of the carb until the slides match up with your adjustments before putting the carbs back on the motor. Namely, the smaller drill bit fits, the next one up don't.

After this, check to make sure the slides are somewhere near flush with the top of the carb at full throttle. And, they should be equal, no matter where they stop.

At this point, you are cooking with gas and are good to go.

That's my recommendation to anyone looking to check or actually calibrate and synchronize their carbs. As always, your mileage may vary and so could the actual procedure recommended by your manufacturer. But, you should be able to use this principle no matter what the actual procedure actually is.
 
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