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Discussion Starter #1
I have a formula that runs great and pulls hard however, I had it on the river yesterday and no matter how long I stayed at WOT it would not past 7000 rpm's. Is this normal or is there something wrong with gearing or clutching or ?. The tach goes up to 9k and I was just curious.
Thanks
John
 

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I asked a sledhead that very question! his answer: horsepower peak is at 4000 to 6000 RPMs. as the the clutches engage the rotation gets more difficult. there is a point where you top out on speed/RPM/rollong resistance. hope that this answers your question
 

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What are you getting for top end speed?

Maybe your tach is just pooched if it is pulling hard.?
What is your top speed like on speedo?

I had a 96 FIII (stock) and me thinks she used to spin around 8500. (Your HP peak is a lot higher than 4-6000rpm btw)

I would guess check your belt, clutches, a stopper bloking your throttle (jk)...
 

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Discussion Starter #4
The throttle only goes to about an inch away from the bars, however when pulling the cable at the carbs they are fully open. It seems to pull very strong all the way to 7k, thats why I thought I would ask. The speedo does not work but my friend on his xlt said his speedo read 95 and I just walk away from him so as I said before I was just curious.
Thanks for the replies
John
 

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My FIII used to read aprox 180kph on speedo (ideal conditions). So if you are walking away from him at 95 (mph I assume) then it sounds about right. As for your speedo not working it is probably just the cable that runs from the speedo to the jackshaft.

Have you replaced any bearings (jackshaft) lately or have just recently picked up the sled? The tach I think works off a magnetic sensor rotating round and round. If one of the magnets dropped out it may no be reading correctly. It is also located around the speedo cable and if it was tinkered with may explain your problems. What does your tach say your sled idles at?
Should be around 1500-2000 I think.
 

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Discussion Starter #6
It idles at around 1800, but what I noticed today is the clutch does not engage until about 3700, is this normal? Its just hard buying something used and not knowing what has been done to it. The only thing I know for sure is that this sled is very powerful.
Thanks for all the imput
John
 
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