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Discussion Starter · #1 ·
I've had this problem since I bought the sled two years ago. Sled had 1050 miles on it when I bought it. It has plenty of power from idle to half throttle, but get to WOT and there is no more power; kind of like cutting out/bogging/not getting fuel. It pretty much can get to 7500 rpm and that is it. I originally thought it was the clutch, but I took that all apart and everything looked good...new belt too.

Now, from everthing I have read it seems like a fuel delivery problem. Took apart the carbs and everying looked brand new. Took out all the jets and blasted them with carb cleaner and compressed air just for good measure. Got it all back together and same problem. Starts a lot easier with the newly cleaned carbs, however!

So...I was thinking fuel pump...pull that off and apart and everthing looks great, no stretch off the diaphram, no tares...looks like new. Blew into the intake line back into the tank and I can blow bubbles freely, so no obstruction there. Put everything back together and sled behaves the same.

Someone mentioned the idle air screws, but I have not messed with them, nor does it look like there is easy access to them now that everything is back together.

I am pretty much out of ideas! Does anyone have any?!?! This is a great sled, I just can't get full power out of it...wich really sucks now that there is deep snow; I am afraid of getting stuck running around at half power.

Thanks in advance for any help!
 

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Toss in a new set of plugs, take it someplace you can run it and run it WOT for a bit, then let us know what the plugs look like. You could be jetted way rich or way lean.

Also, it could be a weak clutch spring.
 

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Discussion Starter · #5 ·
Ugly_old_Poo_kid said:
Toss in a new set of plugs, take it someplace you can run it and run it WOT for a bit, then let us know what the plugs look like. You could be jetted way rich or way lean.

Also, it could be a weak clutch spring.
If it is a jetting problem, would I just change the main jet that the needle goes through? Not looking forward to having to yank the carbs out again...
 

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just had this problem yesturday. 97 xklt 580 could ony go 65-70 mph at wot. bogged out on me bad and it had plenty of low end but top was shot. drove her in the garage and got new plugs and then got back to wot and 80-90 mph no problem and she had tons of power back.

id try the new plugs ngk br9es
 

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If you have the carbs apart again you might want to pressurize the needle and seats and make sure they working right. Also make sure your exhaust outlet isnt bent or dented. It only takes a little bend to choke these things, and they will run like $hit on the top.
 

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I had the same problem, it would bog down at around 70, or when i cracked the throttle even around 40 if i just held it wide open. This worked for me, spark plug boots, see how easily they pull off, or if your plugs have screw off tops that can be it. It doesnt sound like much but I was told its a common problem with some Polaris sleds (as it was with mine). Try getting a set of after market boot plugs, they are 3 or 5 dollars at the most. I got mine at the local Polaris place in Wi. Cut a little ways back on the plug wires just to start with fresh wire and try the new caps. Worked AMAZING on my sled.
 

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check jetting wih a newset of plugs. go wot and kill it. check plugs for proper color. if they look good then check your primary and secondary clutch. had a indy 500 that i could only get to 65mph the primary spring broke about a inch off and didnt even know it.
 

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Is wide open throttle still allowing the motor to run? There is a difference between bogging and cutting out. The machine has a system built in that will shut the motor off, no spark at all, if the throttle is not adjusted properly. I have see the same system with a switch that worked it's way out of it's mount so the sled ran perfect till half throttle, then it shut off. You can unplug this sytem to isolate if it is a problem.

If it was a fuel delivery problem you would not be able to maintain a constant 7500 rpm, things would waiver as fuel supply caught up with reducing rpm's then rev back up again.

A leaking needle and seat could cause good performance down low but kill the motor up high.

You could be having poor performance down low and not be realizing it since reduced power will be more obvious when wind, drag and friction increases with higher speed. I have seen identical sleds perform the dame on low end but one beat the other on top due to carb/motor problems.

Make sure the basics are in place. Proper compression on all cylinders, clean fuel, clean carbs that are adjusted properly and in good mechanical condition, clean clutches (take apart, clean and inspect) both primary and secondary, proper size belt (length and width).
 
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