I have converted my 97` Summit to a Arctic Cat M series 153x15x2.25 Challenger track, I bought the Wahl Bros 7 tooth 3.0pitch antirachet drivers (1 1/4 shaft size). my sled had a 136 suspension with rail extensions to 151 track and I had to move the skid back one more additional inch to take up the slack difference from the 151 it had on it to the 153 I put on it. Of course to make this fit the sled has to have a Drop and Rolled chaincase which mine already did when I bought the sled from my buddy.
I really like how the sled performs and the track works, the extrovert drivers are a bit noise but I don`t really mind it. I have heard the Avid drivers are possibly better and less noisy.
I did this cause the 3.0 pitch 153 and 162 track seem pretty easy to find and plentyfull, the drivers seem spendy while you do this coversion but I think are worth it.
If you decide to do this, look for a track that came off a sled that didn`t have reverse, the reverse tracks have pretty small lugs on the very outer part of the track where most track have all the same size, you have to atleast cut everyother one off so the drivers don`t walk over them, it works but a non reverse track would probably be better but they both work.
Good Luck, Wilcard28