Not sure what I was thinking, but I decided to put 12" wheels on the rear of my 325 Magnum. It came with 10" rears with the 4/4 bolt pattern. I wanted to change tires and get rid of the 489s that came on it. As I over thought the process, I decided to try to change the bolt pattern on the rear to the more common 4/156 which would allow me to use a 12" wheel since I had the stock steel wheels from my 600 sitting in the shop. I read about swapping the rear hub from an '03 Predator then adding spacers to make up the width difference. Used hubs are harder to find, but you can get them from Polaris for about $70 each. Add spacers for another $70 a pair.
I went back through the threads and found a forum member with the CAD drawings for a spacer/adapter. He was willing to share them and I have a good friend who is a tool maker who happens to have an end mill. He was going to have the time and likes a challenge so we made 2 sets. It was cheaper to buy the material stock in a 12" length instead of by the inch so I ended up with enough material to make the second pair. Material was just under $230 so the 4 adapters end up about $58 each. Add new wheel studs and 1/2" socket head bolts and nuts and the 2 complete sets are between $140 and $150 each. Labor and the machine time was free although I bought dinner for them.
The first photo is the way the machine started. It's an old photo when I had the plastics off, but you can see the deeper dish on the rear wheels.
The next photo is the adapter installed on the left rear. It's 2.5" thick so it makes up 5" of track width. The next two photos show the 25" tires which is up an inch from the stock. First is proof of concept with a set of OEMs from the 600 which are shot but showed me that they would fit and the machine could pull them. The next is the tires I finally decided on. This machine is mostly used around my property and maybe once a year on the trails so I went with this Sedona Coyote. They are 6 ply and only available in 2 sizes. 25" for ATVs and 27" for SxS machines but the retail price is less than $400 for a set. The last is the tread for the new tires.
The MOSE Magnum came with black wheels, so maybe this winter I will paint these.
Not sure why some of the photos uploaded sideways. They do end up right side up if you click on them though.