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Discussion Starter #1
I have a 1999 mm 700, that was moved from Alaska to MN. The jets were tuned to MN, but it bogs once I hit 60/65, and won’t go above that. Any help would be appreciated as to how to fix it
 

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What was the elevation before/after? Shift RPM?

The clutching is sensitive to altitude as it's dependent on the engine's HP. As you go up in elevation, HP decreases with air density, so the clutching needs to be setup less aggressive to achieve the same shift RPM as at sea level.
 

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Discussion Starter #3
The elevation in Alaska was 1900 feet above sea level, and now in Minnesota it is 1260 feet above sea level. It engages at 5000 rpm, and it bogs at 7000, and I can go up to 9500, but the speed doesn’t change. The gaskets bad, but I don’t think that’d make any difference.
 

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The clutching definitely needs work if its getting up to 9,500 rpm, it shouldn't be any higher than 8,600 rpm on a stock pipe.

Check the exhaust for a mouse house too, I've had an exhaust restriction cause high speed issues before as well.
 

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Discussion Starter #7
The clutching definitely needs work if its getting up to 9,500 rpm, it shouldn't be any higher than 8,600 rpm on a stock pipe.

Check the exhaust for a mouse house too, I've had an exhaust restriction cause high speed issues before as well.
Yea, the clutch was fine, my gauge is just wonky. I haven’t checked the pipe, thanks!
Also, what does this switch that goes from the top of the engine block back to the carbs do? It’s been switched off this whole time
 

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Not too mention the airbox. Every year I clean mine out from them stupid mice making a nest in both of our Polaris machines. Even with kill traps all over the place and poison little sob's still manage to survive and do that.
 

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That switch is a coolant valve for the heated carbs. It prevents them from icing up, I haven't found it to have much affect on how they run otherwise.
 

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Discussion Starter #10
That switch is a coolant valve for the heated carbs. It prevents them from icing up, I haven't found it to have much affect on how they run otherwise.
Alright
So what do you think is stopping me from going faster?
 

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What do the plugs look like? Next time you are out and it's bogging, without taking your hand off the throttle, kill the engine and coast to a stop. Pull the plugs and tell us what they look like. That can help diagnose a fuel issue...
 

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What do the plugs look like? Next time you are out and it's bogging, without taking your hand off the throttle, kill the engine and coast to a stop. Pull the plugs and tell us what they look like. That can help diagnose a fuel issue...
I will do that
 

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I would do it with new plugs though so you get a more accurate reading. Run it up as fast as you can get it for a few seconds and do what Dan said.
 

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Discussion Starter #14
What do the plugs look like? Next time you are out and it's bogging, without taking your hand off the throttle, kill the engine and coast to a stop. Pull the plugs and tell us what they look like. That can help diagnose a fuel issue...
They were black except the middle ones
 

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For one: whats the need to go that fast? But it sounds like the engine is not at the proper RPM or belt slipping. Does it make a screeching noise when riding?
 

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Is the belt too loose or worn Not getting a full shift or are either of the springs broken or wrong?
 

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Discussion Starter #17
For one: whats the need to go that fast? But it sounds like the engine is not at the proper RPM or belt slipping. Does it make a screeching noise when riding?
It’s not fun getting passed on a lake😂
But no, it sounds just normal
 
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