Polaris ,Yamaha, Arctic Cat,all make 4 stroke 750 twin that make well over 100 hp right now for there sled and PWC line up ,if anything they purposely put detuned 70hp 750-1000 motors in there ATVs for safety and law suits reasons.

The 750 Polaris Switchback makes 80hp in the non turbo version,and 140hp (top pic) with a tubo charger, will polaris put one in a ATV?,not likey. Polaris also has a 150hp 800cc. With these xp850cc ATV only making 70hp Polaris is sure holding back if anything.
Same with Arctic Cat they make a 160hp 800cc (Bottom pic) 4 stroke twin for there sled but there 1000cc ATV only makes 70-75hp. They have there reasons.
http://www.snowmobile.com/manufactur...eview-691.html

http://www.snowmobile.com/manufactur...view-1048.html

 

So you want a Yamaha

I just want a two up Grizz with a 750 v twin EFI engine with enough rack room to carry gear on!

 

I like the high rpm smoothness of a twin on open logging roads but I like the instant low rpm burp the throttle torque of a single on slow rough trailers.

 

my yamie has 150 hp but you won't se that in a big bear for sure lol.

 

Well, the ATV makers try and produce what folks will buy the most of.....and right now, one of the main criteria is POWER. For me it's not about that....but alas, I am in the minority. I like good torque, and enough speed to get up to about 50 to 55. Any more than that and I don't have a good reason for it. I don't race anybody, I'm not into showing off, I don't expect a quad to have the power of a Jeep or pickup, I don't like crappy mpg's, and I don't want a bigger, heavier, ATV on tight trails that has the throttle response of a rocket engine. Not practical nor comfortable for me. I want ruggedness, reliability (as like most Honda's), quality materials, comfort, adequate torque, simple oil changes, and great trail manners (while being good for farm work too). I have hope my new 550X2 will provide all that. So far I'm worried about the recall and a possible ADC noise. We'll see.

 

Not to be brand loyal but EVERTHING you just pinted out DOES point straight towds a Yamaha Grizzly 550! Just saying! Happy trails!

 

And a half dozen other quads.

I read somewhere that the 850 motor was tested to 150 HP, but was detuned for reliability and liability. I wish they would publish torque numbers, though.

 

I think an EPS 850XP X2 is in order...doesn't seem like it would take many resources at all really so it wouldn't take anything away from perfecting the line. I do think a company should get most of the bugs worked out of one new line before totally chaning another line
Kind of like the RZR4,some of those resources could have been put to better use JMO.

 

IMHO there is only one choice that matches his needs! All MFGS esp Yamaha, Polaris,Artic Cat...... are capable of hi HP numbers all you have to do is look at ther snomobile lineup!

 

perfect except for the polaris part lol..