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Discussion Starter · #1 ·
Hi guys! I just bought a used 2009 Polaris Dragon 800 from one of my dads friend today!
I’m brand new to sledding but worked on tons of 2 stroke motors in the past and i’ve got some questions if you guys don’t mind.
So about the sled, the guys put the Artic cat Fix it kit in it and new top end in it and new thermostat etc. He said he has only ridden 25 times in the last 5 seasons. He’s a genuine guy and not one to ride the crap out of his machines. sled starts in 2 or 3 pulls cold after sitting all summer and starts right up when warm. I did a compression test on the motor and it’s reading 92psi in each cylinder. Is there a decompression thing on these sleds like on some motorcross bikes? 92 seems a bit low but I could be wrong. When I pull it over slowly the motor feels very healthy. When I pulled the plugs out both have a even golden brown burn on them.My Elevation is 1600ft above sea level.
Hopefully I can get some information on what’s happening with the motor, I’m mechanically inclined so doing top end or rings doesn’t faze me.
thanks guys!
cheers :)
 

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Discussion Starter · #2 ·
Hi guys! I just bought a used 2009 Polaris Dragon 800 from one of my dads friend today!
I’m brand new to sledding but worked on tons of 2 stroke motors in the past and i’ve got some questions if you guys don’t mind.
So about the sled, the guys put the Artic cat Fix it kit in it and new top end in it and new thermostat etc. He said he has only ridden 25 times in the last 5 seasons. He’s a genuine guy and not one to ride the crap out of his machines. sled starts in 2 or 3 pulls cold after sitting all summer and starts right up when warm. I did a compression test on the motor and it’s reading 92psi in each cylinder. Is there a decompression thing on these sleds like on some motorcross bikes? 92 seems a bit low but I could be wrong. When I pull it over slowly the motor feels very healthy. When I pulled the plugs out both have a even golden brown burn on them.My Elevation is 1600ft above sea level.
Hopefully I can get some information on what’s happening with the motor, I’m mechanically inclined so doing top end or rings doesn’t faze me.
thanks guys!
cheers :)
Okay so i used a different compression tester and it reads 112 on each cylinder now, but if you guys got any tips about sledding please drop them my way!
 

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That sounds low still but you can run it and see how it is. Was that tested cold ? I'd check it hot too.

As for sledding to a newby. Just remember the brakes don't grab the ground like a car can on dry pavement. Riding on snow makes it all slippery. Good carbides on the front allow you to steer better but increase steering effort.

Good luck on the new adventure.
 

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Discussion Starter · #4 ·
That sounds low still but you can run it and see how it is. Was that tested cold ? I'd check it hot too.

As for sledding to a newby. Just remember the brakes don't grab the ground like a car can on dry pavement. Riding on snow makes it all slippery. Good carbides on the front allow you to steer better but increase steering effort.

Good luck on the new adventure.
Thanks Steve! noted and I will do a test on her hot later today :)
 

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Discussion Starter · #6 ·
I agree with steve. That engine should have at least 150 psi compression. Did you hold the throttle flipper open all the way while cranking, and crank until the number stopped rising on the gauge?
I did 10 pulls with the throttle wide open that’s it. Everything that i’ve read online has been saying 125 is average.
 

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SummitSpeedFly
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Hi guys! I just bought a used 2009 Polaris Dragon 800 from one of my dads friend today!
I’m brand new to sledding but worked on tons of 2 stroke motors in the past and i’ve got some questions if you guys don’t mind.
So about the sled, the guys put the Artic cat Fix it kit in it and new top end in it and new thermostat etc. He said he has only ridden 25 times in the last 5 seasons. He’s a genuine guy and not one to ride the crap out of his machines. sled starts in 2 or 3 pulls cold after sitting all summer and starts right up when warm. I did a compression test on the motor and it’s reading 92psi in each cylinder. Is there a decompression thing on these sleds like on some motorcross bikes? 92 seems a bit low but I could be wrong. When I pull it over slowly the motor feels very healthy. When I pulled the plugs out both have a even golden brown burn on them.My Elevation is 1600ft above sea level.
Hopefully I can get some information on what’s happening with the motor, I’m mechanically inclined so doing top end or rings doesn’t faze me.
thanks guys!
cheers :)

First, what altitude are you at? You have to compensate compression readings for your altitude. Google it, you'll find formulas and charts. That said, I have 2x 700 Dragons, 2007/2008. I live at 10,000' above seal level. Best comp readings I've ever gotten are 95, and that's even after a new top end. They both have run fine for years with those readings.
 

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Discussion Starter · #8 ·
First, what altitude are you at? You have to compensate compression readings for your altitude. Google it, you'll find formulas and charts. That said, I have 2x 700 Dragons, 2007/2008. I live at 10,000' above seal level. Best comp readings I've ever gotten are 95, and that's even after a new top end. They both have run fine for years with those readings.
I live about 1800ft above sea level
 
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