There is more than a decal and clutching to the 850 HO over the older 850. There is a guy on HL converting his '10 850 to a '12 HO. Parts alone were over $2K.

77 HP

 

I seen a new rzr Polaris commercial were the were claiming 80 something hp in there ad.

 

I didn't get a chance to talk with the guy racing the Sportsman 850, but I would guess that he ran it in 2wd.He was racing on a paved IHRA dragstrip that was prepped with VHT so traction wasn't really a concern.I have a couple of friends that race Can Am 800's there and they run in 2wd without any problems.

 

Its got enough power..I love the 800xp..I dont have one but wish i did.

 

never enough power.

 

so the cylinder head is different. what else?

 

what are you comparing? between the polaris 800 sportsman and the polaris XP850???

if so- other then both are 4 stroke 4x4 atv's, they are totally different atv's in every other sense.

 

The clutch on the HO is the same as the 2011 XP 850 and the heads have different part numbers but they share the same camshaft and valve sizes. The exhaust is the same and they have the same size air filter and the pistons, crank and rods are the same. The ECU, map sensor and TPS are all the same. The California Air Resources Board has both the 2011 and the 2012 dynoed at 51.5 kw (69.0348 HP)

 

The 850 HO has larger 40mm throttle bodies and a larger airbox netting 7 hp making it 77 hp.

"All 2012 models featuring the 850 engine receive a new airbox which is combined with new throttle bodies resulting in an approximate nine percent increase in power from prior years. With this new intake package, the 850 engine now delivers delivers 20 percent more acceleration off the line. This combination allows more air to the engine and results in a machine that accelerates faster, provides even more xtreme performance with a clean fuel burn while delivering incredibly smooth power across all RPMs. The power upgrade is available on the Sportsman XP 850 H.O., Sportsman XP 850 H.O. EPS and Sportsman Touring 850 H.O."



No way a piped 400 ex will run with a 850xp. My 850xp will beat my scr400 trail moded and i beat a 800 Outlander (pre hp boost) from a 10 mph roll pulling away up to about 65mph.

 

"All 2012 models featuring the 850 engine receive a new airbox"

Where does it say larger airbox? Why does CARB say they are the same peak HP?