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Discussion Starter · #1 ·
Hi all, my 800 twin is really lagging behind in power compared to how it used to be, it only has 400 miles. It has a boggy feel to it, and really impared acceleration. I've THOUROUGHLY cleaned the carbs thinking it was a fuel problem(just felt like one), but to no avail. My next step is clutching but i highly doubt that. It's geting about 7500 rpm as opposed to the optimal 8 g's. Engine integrity is all good, good compression etc. I've visually checked the function of my choke, and it doesnt stick.... so i'm stuck. Anyone experience similar symptoms? Thanks
 

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You might want to check your power valves. they can get built up with carbon and not work properly. It could also be your secondary clutch but that is highly doubtful. You could try tightening the spring on your secondary.
 

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move your clickers up 2 postions and see how it help, it may be you belt is a littte worn or the spring in the clutch have settled and move the clickers should fix it, if you only problem is rpm and you are at 7500 i bet its the clutching
 

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Is your mahine burning alot of oil ,, might be running to rich on oil to ,, had that problem before someone worked on my machine ,, the choke and oil were open all the way ,causing my machine to bog ,,specially on take offs. Like Tfin said ,, check your plugs,,,
Also try to tight that secondary spring a notch or 2 , to see what it does.
 

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does it idle ok? is this problem just on top end or is it boggy throughout the range
 

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Discussion Starter · #8 ·
Hey guys thanks for the suggestions, here is an update: After checking all the things you suggested, i've come to the conclusion that this this is running incredibley rich... The plugs are black(and becoming chunky), it is boggy throughout the whole rpm range, like a blubbering sound. I checked the choke, and it's not sticking at all, unless it is inside the float bowl i didnt check there. I dont have the book, so i'm not sure what the oil adjustment is, although it appears to be on the most open setting. If someone has that could they please post it? Thanks for the help.

Peter
 

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Discussion Starter · #9 ·
Also, this is a 2001 mxz 800, without dpm. I forgot to add that while letting it idle, if i remove the left plug cap, it has ALMOST no effect on sound/rpm of the engine which may explain this fould plug feeling. The right one when removed will make the engine stall out. The spark seems to be very strong though, so i dont think it's that... i put in new plugs, and that didnt do a thing.
 

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maybe just try and change the plugs, or have u done that already?
 

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pull the left plug and hold it against engine block er sumptin and pull rope, u will see spark if the plug is good and all the electrical stuff is good in there, if u see no spark, u got a good diea where to start
 

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Seems like one of the pistons insn't working wright ,, First of all ,, if she's way to rich , you can simply adjust your carb needles i'd say lower then 1 notch to see difference , if not enough ,, then go 2 notches
What i'd do then is remove your left plug(the one that is fould) drop some pure gas in the plug hole,,, place NEW PLUGS in both holes and crank her up ,,, you might have access oil in your cylinder causing plugs to foul up. That pure gas will take care of that and lowering the needles should lean it up a little more. Check your pipes to see if they are both warm,,, if not and your still running on 1 piston , then there's something wrong with that carb
 

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You're not going to be able to adjust the needle height, if I remember correctly these flat-slides only have one notch, but I have heard of different shims being used - resulting in the same effect.

Both the '01 and the '02 8-hundo's have had a problem with the hood hitting the PTO plug wire and cracking the boot - check yours and make sure your plug wire(s) is OK - I've personally seen it on the Mag side too.

Also, there is a carb sync issue, but I believe that is only on the '02's w/ DPM, and your problem sounds more like spark issues than carbs being in sync.

I know the '01 800 had piston skirt/scuffing issues that is warrantied by Ski-Doo - but again, your issue sounds like its spark related.
 
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