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850 Engine thread (840cc)

Rbott

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If this has already been commented on the 840 thread I apologize.

I'm wondering if the engine was under development for 4 years what improvements were incorporated on the electric start system?

Will it be the old unit or will it indeed be like a motorcycle and integral to the block/flywheel?

I am curious about this as well. Mountainhorse.....do you have any info on it?
 

revrider07

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I am questioning whether we will get the same mapping in the Ecu as in the demo sleds floating around?
 

mountainhorse

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If this has already been commented on the 840 thread I apologize.

I'm wondering if the engine was under development for 4 years what improvements were incorporated on the electric start system?

Will it be the old unit or will it indeed be like a motorcycle and integral to the block/flywheel?

I am curious about this as well. Mountainhorse.....do you have any info on it?

There is a permanent boss cast into the case for the bendix... stronger and more rigid than the bolt on ones of the past... I'm told that the bendix itself is more robust as well.

Still an off engine mounted starter motor with drive cable on the 850.

You can see in this photo, the bendix mount boss between the front PTO motor mount and the exhaust pipe, a two bolt flange.... that's for the starter bendix assy.

I was hoping for a mini gear reduction Hitachi style starter to shave some weight... not the case here. :face-icon-small-dis


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phatty

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All new patent pending combustion design helps with the torque. One of the noticeable differences on the 850 was the grunt all the way through the throttle vs the 800 which we all know the power doesn't hit until like 8k rpms.

I think people will be really surprised at how much better this motor really is in all aspects. We can talk numbers and specs all day, but the reality is we only care how it rides, pulls, handles and Polaris hit a home run with this sled.
 

goridedoo

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All new patent pending combustion design helps with the torque. One of the noticeable differences on the 850 was the grunt all the way through the throttle vs the 800 which we all know the power doesn't hit until like 8k rpms.

I think people will be really surprised at how much better this motor really is in all aspects. We can talk numbers and specs all day, but the reality is we only care how it rides, pulls, handles and Polaris hit a home run with this sled.
Horsepower is a stupid thing that so many people get caught up in... every engine, dyno, and set of conditions are different. 3-5 hp is so irrelevant when deciding which new sled to buy, even 10 honestly. If it rips, it rips.

Oh and if your buying a turbo and your first question is “how much HP?” ... you probably dont need one.
 

XCaSSAULT

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I wonder since the ecu tracks fuel changes if it will know that a fuel controller was making changes?

Take pipe and controller off before bringing in for warranty. Digital wrench tells a tale of fuel map fiddling and your s.o.l:face-icon-small-con
 

Scott

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All new patent pending combustion design helps with the torque. One of the noticeable differences on the 850 was the grunt all the way through the throttle vs the 800 which we all know the power doesn't hit until like 8k rpms.

I think people will be really surprised at how much better this motor really is in all aspects. We can talk numbers and specs all day, but the reality is we only care how it rides, pulls, handles and Polaris hit a home run with this sled.

So true.
I know it's hard to do, but people just need to trust and believe when we say "IT'S GOT MORE POWER AND TORQUE!"

You'll see.
 

mountainhorse

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I have Zero doubt it has more power and torque...

With the same bore, 85mm, as the 800 cfi ... the 850 has a wider bore spacing (more transfer port area), more 'case volume', larger stroke, slightly longer rods, improved engine management/sensors...

If it didn't have more overall power... I think there would be a lot of people in Roseau and Osceola on the unemployment line :face-icon-small-win :face-icon-small-con





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mountainhorse

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I believe times are changing.

I wonder since the ecu tracks fuel changes if it will know that a fuel controller was making changes?

Take pipe and controller off before bringing in for warranty. Digital wrench tells a tale of fuel map fiddling and your s.o.l:face-icon-small-con

Most likely it will be more challenging for aftermarket 'piggyback' controllers to deal with this new ECU.

But, since Polaris seems to like their sleds on the RMSHA podium... I'm sure they will work it out :face-icon-small-win

Hacking the ECU will be harder I've heard, and none in private hands yet... unless there is an 'intentional leak' behind closed doors.

Turbos and 'add ons' will be more and more difficult as years go by.

IMO.




 

XCaSSAULT

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Most likely it will be more challenging for aftermarket 'piggyback' controllers to deal with this new ECU.

But, since Polaris seems to like their sleds on the RMSHA podium... I'm sure they will work it out :face-icon-small-win

Hacking the ECU will be harder I've heard, and none in private hands yet... unless there is an 'intentional leak' behind closed doors.

Turbos and 'add ons' will be more and more difficult as years go by.

IMO.





Right. Well the envelope is getting pushed harder and harder right from the factory. If this 850 really is let’s say 168 horse and motor weight I’m guessing is around 150#’s that’s more then one horse per pound power to weight ratio! That’s pretty mind blowing when u think about it. I don’t think anything else (on the planet) can give that kinda power/weight ratio.

How far can the twin two stroke be pushed (on a large scale manufacture, warranty-able scale) are we nearing the limit?

I couldn’t imagine any of the 3 sled manufacturers selling a factory turbo which was rumored before March 5. Wouldn’t be cost effective. 220 horse 850 turbo that will go 4,000plus trouble free miles. No way I say. Maybe if u start incorporating some titanium in the mix. Think of what that would do to the price of a sled!

Point I’m making is the aftermarket world has a hell of a challenge ahead of it. Can a pipe and fuel/timing box add 8-10horse reliably when polaris already has this motor near its limit?

It sucks we gotta wait 8-9months to find out!
 
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Old & slow

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Right. Well the envelope is getting pushed harder and harder right from the factory. If this 850 really is let’s say 168 horse and motor weight I’m guessing is around 150#’s that’s more then one horse per pound power to weight ratio! That’s pretty mind blowing when u think about it. I don’t think anything else (on the planet) can give that kinda power/weight ratio.

How far can the twin two stroke be pushed (on a large scale manufacture, warranty-able scale) are we nearing the limit?

I couldn’t imagine any of the 3 sled manufacturers selling a factory turbo which was rumored before March 5. Wouldn’t be cost effective. 220 horse 850 turbo that will go 4,000plus trouble free miles. No way I say. Maybe if u start incorporating some titanium in the mix. Think of what that would do to the price of a sled!

Point I’m making is the aftermarket world has a hell of a challenge ahead of it. Can a pipe and fuel/timing box add 8-10horse reliably when polaris already has this motor near its limit?

It sucks we gotta wait 8-9months to find out!

The main difference is aftermarket company's aren't regulated. So until the tree huggers force compliance the aftermarket has an advantage, it may be getting narrower but its still there.
 

iluv2fly

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Right. Well the envelope is getting pushed harder and harder right from the factory. If this 850 really is let’s say 168 horse and motor weight I’m guessing is around 150#’s that’s more then one horse per pound power to weight ratio! That’s pretty mind blowing when u think about it. I don’t think anything else (on the planet) can give that kinda power/weight ratio.

How far can the twin two stroke be pushed (on a large scale manufacture, warranty-able scale) are we nearing the limit?

I couldn’t imagine any of the 3 sled manufacturers selling a factory turbo which was rumored before March 5. Wouldn’t be cost effective. 220 horse 850 turbo that will go 4,000plus trouble free miles. No way I say. Maybe if u start incorporating some titanium in the mix. Think of what that would do to the price of a sled!

Point I’m making is the aftermarket world has a hell of a challenge ahead of it. Can a pipe and fuel/timing box add 8-10horse reliably when polaris already has this motor near its limit?

It sucks we gotta wait 8-9months to find out!

There is no way polaris built this thing to the limit. I think pipes and fuel boxes will get another 10hp.
 

XCaSSAULT

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There is no way polaris built this thing to the limit. I think pipes and fuel boxes will get another 10hp.

I wasn’t “necessarily” saying poo built this 850 to its limit. I’m no engineer but how much “reliable” power can a high volume sled manufacturer squeeze out of these twins? Polaris, Cat, or Doo?

Yes of course u can add a turbo, big bore, both, nitrous! Lol, and get much more power, but your taking years of life off the motor.

Just like building a chev small block...add enough power and a two bolt main ain’t gonna cut it.

There’s a “perfect combo” of bore and stroke with any motor. I believe the liberty 700 had that perfect combo. The 900 obviously did not and I don’t think the 800 ever did either. Maybe this 850 will. Damn that be sweet if they dropped the 600 and had only a 850 and 700 with all the new updates.
 

goridedoo

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Most likely it will be more challenging for aftermarket 'piggyback' controllers to deal with this new ECU.

But, since Polaris seems to like their sleds on the RMSHA podium... I'm sure they will work it out :face-icon-small-win

Hacking the ECU will be harder I've heard, and none in private hands yet... unless there is an 'intentional leak' behind closed doors.

Turbos and 'add ons' will be more and more difficult as years go by.

IMO.




Vipec? Or will the ecu still need to be hacked?
 

mountainhorse

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Who knows at this point??

But, from what I hear, this Kokusan ECU has the ability to go into limp mode when control signals dont match up with output... being able to detect piggyback controllers... HMMM... may or may not be true.

Lets see who has this ECU hacked.... or if the numbers make it worthwhile....Also, there is a good chance the Validation ECU's will not be the same as the consumer/production sleds we get next fall.

Time will tell, but there are some "smart cookies' out there.




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