• Don't miss out on all the fun! Register on our forums to post and have added features! Membership levels include a FREE membership tier.

Converting my ‘17 driveshaft

L
Nov 13, 2012
66
15
8
Waverly, MN
Converting my ‘17 driveshaft

So I landed on a rock and snapped my driveshaft on my ‘17 PRO RMK with the 2.6. From what I can tell if I wanted to swap to the steel driveshaft off a 2012 Pro RMK or similar they have the same pitch 2.86, but different drivers one 7 one has 8? Would I have to get aftermarket drivers from Avid then to fit the steel shaft with the 7t?

Thanks
 

sledhed

Well-known member
Lifetime Membership
Premium Member
Dec 19, 2001
1,749
435
83
Lolo, Montana
Go 8-tooth... IMHO

I recall when the Axys first came out many (at least in Missoula area, Kurts Polaris guys told me) were switching to 8 tooth drivers. Better approach angle for the snow and more efficient turning the larger diameter... plenty of clearance to run it with the 2.6 track. Might need to gear the sled down then with a set of Pro QD gears but that is commonly done.

Or just pick up a used driveshaft with stock drivers off the facebook "mountain sledder swapmeet" group...
 

richracer1

Well-known member
Lifetime Membership
Feb 2, 2011
3,626
2,480
113
Idaho Falls, ID
To do this swap:


1) You can keep the 8T stock drivers but will need to change out your QD sprockets to the Pro-Ride sprockets and still use the Axys QD belt. Personally I'd go with Avid 2.86 drivers either with 7T or 8T. If you do the Avid drivers and do NOT want to trim the rails back, get the center extrovert driver set up from them. I installed a Kmod skid before my 16 Pro-RMK saw any snow, so I got the other style an no rail trimming was needed.



2) You will need to get the short bolt for the lower QD sprocket. It's 20 or 25mm in length to use the steel drive shaft. I would get some ARP bolts to replace the stock QD sprocket bolts. You will need to get some bolts for the PTO side bearing flange. I believe they are 8mm. The Axys RMKs have studs on the flange.


3) As your installing the lower QD sprocket, put a good amount of either grease or anti-sieze on the shaft splines. You'll be thankful you did if you need to remove the sprocket.


I ordered a new steel shaft that comes on the chaincase equipped Axys RMK/SKS sleds and installed Avid 3" pitch drivers to go with the 3.2" track. The weight difference from the "lite weight" aluminum shaft with Avid 8T 2.86 drivers to the the steel shaft with Avid 7T 3" pitch drivers was around 4 to 6 OZ.
 
Last edited:
L
Nov 13, 2012
66
15
8
Waverly, MN
If I keep my 8t drivers they won’t fit on the steel shaft though will they? Because of the different shape of the shafts? So I would have to no matter what but Avid drivers to fit on the steel shaft? I haven’t quite got all the driver and pitch all figured out. If there the same pitch 2.86 a 7t won’t fit A 8t track correct?
 

Sage Crusher

Well-known member
Lifetime Membership
Dec 30, 2010
3,261
1,171
113
Rock Springs,Wyoming
Just keep this in mind-as I ran the 8 tooth drivers for 2 seasons with the 2.6 track....
It fits fine, but snow evacuation is greatly reduced in the front of the tunnel- Yes approach angle is flattened....

I ended up going to a 3" pitch track and 7 tooth Avids .... with the K mod suspension and Ice Age rails there is zero need to cut rails.

You should be able to find pretty easy 7 or 8 tooth splined ( chain case) or HEX ( QD) drivers... I have a set of 7 tooth HEX (Quick drive) you can have

Robbie @ Avid has either splined or Hex style drivers... 7 or 8 tooth in the 2,86 no problem there......but if your running stock rails,they will have to be trimmed ( cut back) to allow the extroverts plenty of room... I for one don't like running the center extrovert only style .. We have found it to ratchet under load and has zero clips

Your getting a bit confused on 7 tooth vs 8 tooth
 
Last edited:

richracer1

Well-known member
Lifetime Membership
Feb 2, 2011
3,626
2,480
113
Idaho Falls, ID
Just keep this in mind-as I ran the 8 tooth drivers for 2 seasons with the 2.6 track....
It fits fine, but snow evacuation is greatly reduced in the front of the tunnel- Yes approach angle is flattened....

I ended up going to a 3" pitch track and 7 tooth Avids .... with the K mod suspension and Ice Age rails there is zero need to cut rails.

You should be able to find pretty easy 7 or 8 tooth splined ( chain case) or HEX ( QD) drivers... I have a set of 7 tooth HEX (Quick drive) you can have

Robbie @ Avid has either splined or Hex style drivers... 7 or 8 tooth in the 2,86 no problem there......but if your running stock rails,they will have to be trimmed ( cut back) to allow the extroverts plenty of room... I for one don't like running the center extrovert only style .. We have found it to ratchet under load and has zero clips

Your getting a bit confused on 7 tooth vs 8 tooth

I don't like the center extrovert driver set up either.
 
L
Nov 13, 2012
66
15
8
Waverly, MN
Your getting a bit confused on 7 tooth vs 8 tooth

It doesn’t take much

I’m not looking for aftermarket really just want to replace as stock just cheaper. So if I understand it a pro chassis RMK with quick drive would bolt right in but I would need different bolts to attach the belt drives? And a steel shaft RMK would fit but I would need pro chassis belt drives to achieve the same ratio?
 

Sage Crusher

Well-known member
Lifetime Membership
Dec 30, 2010
3,261
1,171
113
Rock Springs,Wyoming
It doesn’t take much

I’m not looking for aftermarket really just want to replace as stock just cheaper. So if I understand it a pro chassis RMK with quick drive would bolt right in but I would need different bolts to attach the belt drives? And a steel shaft RMK would fit but I would need pro chassis belt drives to achieve the same ratio?

You can P/M me anytime....
 

sledhed

Well-known member
Lifetime Membership
Premium Member
Dec 19, 2001
1,749
435
83
Lolo, Montana
If I keep my 8t drivers they won’t fit on the steel shaft though will they? Because of the different shape of the shafts? So I would have to no matter what but Avid drivers to fit on the steel shaft? I haven’t quite got all the driver and pitch all figured out. If there the same pitch 2.86 a 7t won’t fit A 8t track correct?
Whether 7 tooth or 8 tooth, if your track is 2.86 inch pitch and you want to keep that track, you have to stick with 2.86 pitch. Regardless of tooth count. And regardless of whether you go with hex or splined shaft. If you have a splined style shaft to put back in there with 8 tooth 2.86 pitch drivers, the easiest solution IMHO would be to just put it in there and run it. Realizing it gears you up, but that gets you back on the snow. You can gear it back down using one of the many alternatives; cheapest is to us PRO quickdrive pulleys along with your stock Axys belt. Or you can go with a Kurts gear down, or TKI, or the one from Canada which I forget the name.

Disadvantage of 8 tooth: gears you up (which you can fix - above) and reduces snow evacuation (but no worse than 2011-2015 Pro I believe).
Advantage of 8 tooth (stock style) drivers: lower track rolling resistance (larger diameter), and I am sure there are other advantages I am forgetting. Should not need to trim rails.

Just an FYI, I bought the 7-tooth involute style drivers from Avid and put them on my 2015 Pro QD hex shaft before Polaris even came out with the Axys 7-tooth, so I could gear it down without gearing it down. Using the close-to- stock style meant no trimming rails and no antistab needed. I ended up picking up a Kurts gear-down setup cheap and went back to stock 8T drivers and sold the Avid 7T (and took a bath on that, but hey, that is sledding).

So if you don't want to fool with gearing etc., stay stock 7T 2.86 pitch with either hex or splined drive shaft depending on what you can find for sale... for a little more punch off the line and in the mountains, for the 7 tooth setup, pick up a used set of quickdrive gears off a 2013-15 Pro, which will work with your stock Axys QD belt. I have sold a number of sets of those myself, they go for $130-150 typically, seen some for sale on facebook's "mountain sledder swapmeet", separately or as part of Pro part-out sales...

Hope that helps.
 
Premium Features