Sounds like you might as well go with the 850 if your doubting. But with the power of the 850 why add pipe,fuel controller, etc.? I can see tires, bumpers and what-not but HP upgrades? The 850 has more power than most guy's will ever need or use. Or do you just want to be able to say mines bigger than yours?

 

I have a '09 550 and I love it. Never ridden a 850 but I also never needed anything more than the 550 can handle so I'd consider the upgrade, for me, pointless. Since the 500's came out in '96 we have had a total of 10 atv's, 8 of those were sportsman 500's and 2 '09 550's. We ride a lot of open trails, with long straights and a good mixtures of soft dirt and rocks. I've had my old '96 sportsman 500 up to 62mph (gps) going on a slight downgrade, WAY to scary for me to go that fast, I've gotten my 550 up to around 60 but never "maxed it out" yet. I bought the 550 over the 850 due to the fact I'll never drag race it (I'd buy a outlaw or raptor for that) and I'd never put a ginormus lift and big tires on it (I have a 1 ton big block bronco for that).

Sooooo If you plans on drag racing or wanting to put 32" silver backs on it then I'd probably go with the 850 but if not a 550 will do everything you need it to do.

 

For me i don't NEED the 850's power but I love it.
I ride for the thrill of riding I guess maybe it's still the young and dumb part of me I like punching the gas and feeling it pull hard. I still like throwing my leg over a CR250 from time to time just to feel like i'm still alive. Power is fun but is it needed not really. But I still love it enough to pay the extra for the thrills.

 

well, I went by the dealership and they let me test ride each one, and i think my mind is made up. 2011 US VIN Stealth Black 850 its on hold, woot. I am lost with the comments about it being squirrely or not as agile, i think the rider makes the difference, but to each there own, I now at least have mine picked out. Now if the tax money would just get here already so i can take delivery.