01Grizz:
Don't know how big of tires would fit. It comes with 25 inchers, and I know there is an easy 1 1/2 to 2 inches of clearance left after bottoming, at least in the back. I would say 26" for sure, maybe 27. I am still running stock as I have yet to get stuck (knock on wood).
Rear shaft drive? Haven't heard either way. I have heard that on the '01 machines the speedo is an option, not standard.
Our local dealer is selling out his remaining 00 Xplorers for $4999 - cheap enough to justify a pipe, porting, & etc, if you get my drift.
Stock, the Xplorer has about as much engine as a Grizzly. Less grunt off the bottom, but faster revving, and maybe more wound up.
I had a friend lose some buildings to a tornado last year, and my Xplorer and a neighbors Grizz were the only machines that could roost all 4 tires on grass. I don't mean just breaking the tires loose, I mean having enough wheel speed for a true all around 4 wheel roost! (It is amazing how hard it is to move a garage roof out of a pasture). Not to insult the Grizzly, but put one front tire in mud & one on grass & only one spun. Dragging the front brake got both to turn, but with mine I didn't have to do anything but flip the switch. Also after driving both, the Xplorer is more nimble (but not by a whole lot) and rides quite a bit better.
If you don't need the racks & could live without low range, consider a Scrambler. Same engine as the Xplorer, same 4wd system, but longer travel suspension, and somewhat lighter in weight.
I wouldn't be too scared of the 2 cycle, it is holding up well for me. I have worked it hard from time to time, but also like to just trail ride also. I grease it & oil the chain religiously, and have yet to replace anything after close to 3600 miles, not even the silly plastic steering bushing (I grease that about every 5 hours though). The smoke & smell is all but nonexistant once warmed up if you use the synthetic oil.

 

01Grizzly,

Since you are not fond of 2-strokes...They do have the Scrambler500 4x4 4 stroke! It is the same engine as the Sportsman500 High output. It is a medium-weight sports/trail quad. 22 inch tires in the back and 23 inch up front. Same 4x4 system as all other Polaris models plus switchable 2x4 to 4x4. It's one of the fastest, if not the fastest 4x4 available today. It is a great mudder and can keep up with the other sport quads. Post some questions...a lot of guys in here own them.

It is a great mix between what you are used to and a sports model. It has speed and brawn. Sure it lacks a bit of suspension quality in huge whoops and 5 foot high jumps...but still holds its own. Test ride one!

Brian