I'll stick to the 4-wheeled, non-side-by-side machines.

- Suzuki Quadrunner LT125D (first 4 wheeled atv)
- Honda FourTrax TRX350 (first 4x4 quad)
- Yamaha Banshee (2 cylinder 2-stroke, first true performance quad)
- Yamaha YFZ 450 (first 450 sport quad, made a new racing class)
- Can-Am DS 450 (No welds, all aluminum, hollow axle, inside brake calipers, ahead of its time)

 

I think Suzuki's 1989 250 Quadrunner was the first ATV with both IRS and a true 4wd with diff locking system.

 

My father has one of those. It has two shocks on it, but I thought it was just an articulating axel though I could be wrong. And 4x4 with diff lock isn't the same as AWD which Polaris has.

That 250 is a ton of fun though. And with the super low range, the only limitation on what it can tow is traction and it's own weight. Amazing torque.

As for the first true performance quad? That's not the banshee I'm pretty sure. Fast as all get out, but they don't handle anywhere near as good as the 250r.