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2021 Drivers and Gearing

frntflp

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I really like my '18 800 163 w/Kurts gear down. I'm confused as to the difference in gearing between the new QD2 and a Kurts gear down kit? "At the end of the day", If I buy a 163 or 165 model with the QD2, do I still need to swap it out the gears/belt for a Kurts to get the same geared down result/feel as I have now ? (All assuming non-turbo) TIA !

Looking deeper, here is what I found (and stated on previous page)

2.6 lugs, 2.86 pitch, 22 top/43 bottom - 1.95 ratio (current config or "QD1")
2.75 and 3.0 lugs, 3.5" pitch, 22 top/50 bottom giving 2.27 ratio - aka QD2

Kurts gear down kit is 2.37 ratio.
 
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Teth-Air

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Some food for thought. After clutching and gearing several Pro-Rides and AXYS sleds I have found that gearing down lower than 2.25:1 with stock clutching leaves a lot of performance on the table. When getting down to 2.42:1 (equivalent) or lower the clutching is even more important to change. The 850 with stock clutching and 2020 flash is even worse as gearing down reduces load on the motor. I hope Polaris realizes this and clutches for this gearing change.
 

kanedog

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Yes. The motor needs to be loaded with more helix angle and/or more weights or a combination of both. The engine should sound “grunty” as opposed to “buzzy.”
 

DITCHBANGER

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I really like my '18 800 163 w/Kurts gear down. I'm confused as to the difference in gearing between the new QD2 and a Kurts gear down kit? "At the end of the day", If I buy a 163 or 165 model with the QD2, do I still need to swap it out the gears/belt for a Kurts to get the same geared down result/feel as I have now ? (All assuming non-turbo) TIA !

Looking deeper, here is what I found (and stated on previous page)

2.6 lugs, 2.86 pitch, 22 top/43 bottom - 1.95 ratio (current config or "QD1")
2.75 and 3.0 lugs, 3.5" pitch, 22 top/50 bottom giving 2.27 ratio - aka QD2

Kurts gear down kit is 2.37 ratio.
you are posting the final ratio for kurts(gear ratio and driver size), where as you are posting the actual gear ratio for stock. qd1 and qd2
 

DITCHBANGER

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Some food for thought. After clutching and gearing several Pro-Rides and AXYS sleds I have found that gearing down lower than 2.25:1 with stock clutching leaves a lot of performance on the table. When getting down to 2.42:1 (equivalent) or lower the clutching is even more important to change. The 850 with stock clutching and 2020 flash is even worse as gearing down reduces load on the motor. I hope Polaris realizes this and clutches for this gearing change.
Depends on type of riding as well, Im geared too low according to many, and I'm leaving performance on the table? like what ...top end?
Did a big ride today with a summit, nasty creeks with lots of powder tight bends and tons of pillows to jump off and over, so on and off throttle steady, thats where the lower gearing shines. After a bunch of riding we stopped and checked clutch temps, summit cooking eggs..my geared down poo very mild heat 90-100f. Now if I was climbing straight up long hills then yes maybe lower gearing may hurt.
 

goridedoo

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I really like my '18 800 163 w/Kurts gear down. I'm confused as to the difference in gearing between the new QD2 and a Kurts gear down kit? "At the end of the day", If I buy a 163 or 165 model with the QD2, do I still need to swap it out the gears/belt for a Kurts to get the same geared down result/feel as I have now ? (All assuming non-turbo) TIA !

Looking deeper, here is what I found (and stated on previous page)

2.6 lugs, 2.86 pitch, 22 top/43 bottom - 1.95 ratio (current config or "QD1")
2.75 and 3.0 lugs, 3.5" pitch, 22 top/50 bottom giving 2.27 ratio - aka QD2

Kurts gear down kit is 2.37 ratio.
QD2 with factory drivers and series 8 will be 2.47(final drive ratio) vs your current 2.37(final drive ratio). If you put a Kurts on the 2021 you would be gearing UP.
 

frntflp

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QD2 with factory drivers and series 8 will be 2.47(final drive ratio) vs your current 2.37(final drive ratio). If you put a Kurts on the 2021 you would be gearing UP.

Maybe that's why I'm so confused ..... so the driver on the Series 8 track will be smaller than found on the Series 6?
 

Teth-Air

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Depends on type of riding as well, Im geared too low according to many, and I'm leaving performance on the table? like what ...top end?
Did a big ride today with a summit, nasty creeks with lots of powder tight bends and tons of pillows to jump off and over, so on and off throttle steady, thats where the lower gearing shines. After a bunch of riding we stopped and checked clutch temps, summit cooking eggs..my geared down poo very mild heat 90-100f. Now if I was climbing straight up long hills then yes maybe lower gearing may hurt.

As Kanedog implied, they can get buzzy and feel like they are revving and really not going anywhere fast. They like to be loaded. Remember the secondary is torque sensing. Yes type of riding is important and i'm not implying that yours doesn't work for slower technical riding.
 

BeartoothBaron

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Remember that Polaris literature seems to baseline the final drive around the 8t x 2.86 driver, which is 22.88 circumference or 7.28" diameter. AXYS is 7t x 2.86, giving you 20.02" / 6.37" which is why it had a lower final drive despite a higher quickdrive ratio. A 7t x 3.0 driver (21" or 6.7" diameter, 6t x 3.5 is same as mentioned) gives you an 8% lower final drive than the 8t x 2.86, 5% higher than 7x2.86, but still 9% lower overall going from QD1 to QD2. Confused yet?

On the other hand, you're losing ground against the chaincase in terms of gearing. QD2 is 2.27:1, the chaincase used 19/44 gears, for a 2.31 ratio. And you can drop a tooth on the top gear to get 2.44:1. So QD2 is a great step in gearing over AXYS QD1, not so much for the chaincase sleds. Makes me wonder if, for the money at least, some guys might be better off getting the series 8 track and drivers than buying a new sled.

On the approach angle, @Sheetmetalfab is right that there's no change in the 3" tracks. You should gain just a bit over the 7x2.86. I'm assuming they haven't moved the driveshaft just to confuse everything...
 
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