850 gone down already??

[indydan]

Good call Trueman

Spoken from the expert....geeeeez, Dan, I have major respect for your knowledge and talent, but taking cylinders off any engine is far from easy for the majority of garage mechanics. Please don't do this, unless you really know what you're doing or at least study up on it.

Polaris needs to hire Dan as a consultant. Seems like a no-brainer. Hello, Polaris, you listening?

Don't take your 850 apart ! I would actually love to see Polaris work thru this if the honing is all the same as our 174 850

( Plus you know I just hate this bickering back and forth ) it's not good for positive thinking.

I would much rather be a raving fan of Poaris and work with them.

The problem has always been....... As I experienced at the Mpls/St Paul airport in 2015

Waiting for our private chartered jet to get ready to go to the Big Mazak Factory tour.

It wa early in the morning and I was sitting in a airport bar alone...... And in walked 4 dudes dressed in matching designer jeans....... They were stunning, ( all pretty young )

And they had no clue who I was.... After listening to them for just a few moments I focused on them and I knew exactly who they were .

3 of Polaris's hotshots along with a straggler...... ( if I remember right ) They were just yucking it up and almost breaking their own arms patting themselves on the backs how great they all were between slugs of their $15 double Bloody Mary's

Most of the chatter was about the 800 Axys motor, but there was idle chatter about a new motor comings and how awesome it was !

How could they know anything at that time about great ?

Polaris's arrogance at the top is enough to make a billy goat puke.

What Polaris needs is a united team that pull together like a freight train that listens to the public ( about motors ) not just the chassis.

And they need to remove the blinders.

The 850 is a monster laying in the weeds waiting to be awakened.

850 customers Need to remain positive.... Great days are coming with this motor.

I really do love the motor !!

Dan

 

[BigAir]

Great read and thanks for all the information Dan. Makes me really glad I held off buying an 850 (I don't like buying first year anything). Do you know the rod ratio of the 800 Etec, Doo 850, and Cat Ctec off the top of your head?

 

[ADDIE]

I don't think that anybody is questioning the lower end and cylinder wall lubrication challenges that are a result of the fuel injection system on the Doo and Polaris. There is no doubt you need to be using a a low viscosity oil and lots of it.

The honing finish does not suddenly allow for oil dispersion from the crank webs to the piston and cylinder walls. Lack of fuel and oil anywhere is not fixed with a finer hone finish.
In fact, the argument can be made that the coarser the finish the more oil it can hold. Remember the plating is porous and retains oil.

Yes, some will exit after sitting but the plating is impregnated with it at all times. It has to be because if it were not the rings would seize immediately upon contact to the cylinder once the heat builds.

I know what you have said sounds legit to some, but you are leaving out a few key details about what really happens at a cold start up. Friction is lower with a lower rpm and the oil is retained inside the plating to provide the needed oil barrier to avoid galling.

Dan, without the oil barrier to prevent galling, the piston's life will be short lived. Again, the finish does not suddenly provide an oil barrier film.

It seems the you are claiming that your smoother finish reduces drag when dry and that the cylinder wall is actually dry after sitting? If you believe that the cylinder plating is dry, then this might hold true, but if you believe that the cylinder plating is not dry and has oil impregnated due to its porosity, then the claim does not hold true.
Also, fuel lubricates too.

Maybe call a plating house, and ask them about this. They will know better than anybody. I have also seen pics from a microscope of the plating that actually shows how porous it really is.

There is also an engine term known as Oil Migration. Look that up people it is interesting.

It all sounds good unless until you really think about it and realize that it is not the case. No engine will survive once the oil is depleted. Fine finish or coarser finish. Oil is mandatory to prevent seizure.

 

[indydan]

Rod Ratio

Great read and thanks for all the information Dan. Makes me really glad I held off buying an 850 (I don't like buying first year anything). Do you know the rod ratio of the 800 Etec, Doo 850, and Cat Ctec off the top of your head?

Not off the top of my head ( i have them all in my notes ) but i do know they are all shorter then i like.

I like the 2.0 rod ratio area in a 800 motor.

The case volume goes up ( and the motor gets tall ) I took the rod raito past the 2.0 point in a few Ski-doo 800 XM motors up in Canada where they really ride... and those motors are off the charts for dependability and performance.

Most USA people don't this but the most expensive mosts tested motors i sell go to Canada.

Oil guys ride !! most of them have winters off and they test your product like no one can imagine.

There is an under ground dealler network i sell to in Canada and they have pushed me to pay close attention to detail because if you forget to cross a
( T ) or dot an ( I ) they will find the weak points.

Good rod ratio's make cylinder finish and fuel injector location less important.

The Ski Doo injection system is off the charts KING OF THE INDUSTRY

Thank you Evinrude & Johnson outboard motor corp for inventing that technology.

I gotta go to work !! Damn-it !!

Dan

 

[indydan]

ADDIE

ADDIE

I just saw your post after i posted my last post.

I will answer late tonight.

All good points and almost all true....but you are missing to one key factor that
nakes most of your true points completely invalid.

And i can explain it..... i don't need any help from plating companies or oil engine-hears... ( especialty from those who live and operate in a static enviornment
behind a desk. )

My business took about a 1/4 million dollar loss from piston destruction.......Caused 100% by the cylinder final finish put on by a plating company.

Those are the last people ask about cylinder finish........There to damn busy trying to keep up with failed OEM motors to have time to fine why they have so many come backs.

( Now be careful and read all of this next statement ) - Millenneum who does all my cylinders.... has the worst final finish in the industry ( do you k now why ? )

Not there fault...... the price of stripe and replate.... the time it takes to turn a cylinder thru the entire system from check in to the final ship back to customer does not allow
for them to do a muli-step final honing process.

Millinneum plating AFTER i get done * Torque Plate honing is off charts a great quality plating *

US Chrome ... yes has a WAY better final finish for the single cylinder customer------- BUT they can't handle volume i do of the quality sizing i demand for undersize.

If Millennium did the same final finish i did they would have to charge double for the final product. ( and then their sales would tank )

Becasue very few people understand this story..........and there most often is not enough hours in a day to tell one person......If you have to explain it to all why your price is higher
you will go bankrupt on the phone talking your way to the poor house.

By the way.... that was a good post.

Be back tonight.

Dan

 

[ADDIE]

Dan, you make it seem that the big block and the small block only differ in rod length. We,both, know this is not true. there are many differences that are in play with this topic.

1) Very important. The small block engine does not have 360 degree crank rotation piston skirt support. There are many degrees of rotation where the piston is not fully supported by the cylinder. This causes added side loads, especially, when the piston changes direction at bottom dead center. This is one of the major reasons why the pistons wear.

2) HP differences. You did mention this. The big block engine was capable of very high power output, when modified. You know as well as anybody, once you got the power up on the big block to where it is with the small block, this engine was spitting pistons and bearings and even stretching the cylinder bolts. It was anything but reliable once its power was matched to the current small block. Power is a key player with engine durability. Increase power, you decrease engine life and all internal components will be under more stress.

More stress equals less life.

Stating that the hone finish is a major reason why the big block lasted longer is a stretch and you know it.

Lesser power and more piston support is why it would last in stock form. Again, when this engine was pumped up, it was far from reliable.

You can not compare until the power outputs are equal.

There are many more differences and you know this.

 

[richracer1]

Great read and thanks for all the information Dan.

I totally agree with BigAir.



I know for a fact that Polaris has people lurking around in the Polaris section here. A Polaris guy at the Jackson hillclimbs a few years ago told me so, but also stated the he would NOT divulge his/her/their identities.
I'm sure the bean counters at Poo have probably killed some really good ideas and processes due to it would cut into profits....

 

[indydan]

Dan, you make it seem that the big block and the small block only differ in rod length. We,both, know this is not true. there are many differences that are in play with this topic.

1) Very important. The small block engine does not have 360 degree crank rotation piston skirt support. There are many degrees of rotation where the piston is not fully supported by the cylinder. This causes added side loads, especially, when the piston changes direction at bottom dead center. This is one of the major reasons why the pistons wear.

2) HP differences. You did mention this. The big block engine was capable of very high power output, when modified. You know as well as anybody, once you got the power up on the big block to where it is with the small block, this engine was spitting pistons and bearings and even stretching the cylinder bolts. It was anything but reliable once its power was matched to the current small block. Power is a key player with engine durability. Increase power, you decrease engine life and all internal components will be under more stress.

More stress equals less life.

Stating that the hone finish is a major reason why the big block lasted longer is a stretch and you know it.

Lesser power and more piston support is why it would last in stock form. Again, when this engine was pumped up, it was far from reliable.

You can not compare until the power outputs are equal.

There are many more differences and you know this.

I have customers with small block 800's with turbos.. 200 plus HP

5000 plus miles on the same pistons with low cylinder support... with a longer rod.

Be back tonight.

I'm out of here.

Dan

 

[JJ_0909]

As an analyst I find all of this a bit comical. Not trying to take anything away from Dan's extensive experience, but there are a few things to take into account here....

Dan doesn't seem too positive on any modern Polaris motor. This is interesting because I know of only a handful of blown up 800HO motors, and those were high mileage boosted motors. I know hundreds of 800 HO motors that, when well mantained, have been awesome year over year.

I don't expect a top end to go further than 2K. I don't expect more than 4K from a bottom end. If you have these redone at the right intervals, you can keep riding (and riding and riding) for a long time. Case in point, all the rental shops in Jackson are able to keep their sleds running easily (of all brands) with a fairly limited down rate.

Polaris has a warranty rate of around 1% of snowmobile sales. This is pretty low. Now does this mean they are covering everything? Of course not. Lots of sleds come with 12 month warranties, they weasel out of a few, etc etc.... but then again, this 1% isn't just motors. Its all sorts of things.

End of the day, this is where Dan's logic really falls short. Since the later Pro-RMK era, there really hasn't been a massive problem with motors. There are enough sleds out there Dan will always have a business, but to suggest there is an intrinsic design problem, to suggest Polaris is full of arrogant engineers is a bit of a lie based on numbers alone.

So maybe the 850 is something awfully bad. But I doubt it, I wouldn't bet on it. If there is something wrong with it, it'll be something that happened to a few during assembly (crank bearing in the wrong spot). But to suggest the rod angle, or some other piece of the engineering is off doesn't strike me as likely considering how much we *know* about 2 stroke motor design, and motor design in general. R&D is measured in the hundreds of millions at Polaris. Just think about that...

 

[shattuck]

Thanks Dan for all the info. Is anyone else wondering why Polaris puts their motor work into the hands of the lowest bidder but sponsors all these professional riders maybe they could better spend their money on engines instead of paying all these riders to tell us how great and flickable Polaris snowmobiles are.

 

[JJ_0909]

Thanks Dan for all the info. Is anyone else wondering why Polaris puts their motor work into the hands of the lowest bidder but sponsors all these professional riders maybe they could better spend their money on engines instead of paying all these riders to tell us how great and flickable Polaris snowmobiles are.

I am in the unique position to know what one of those contracts is worth. Its pennies on the dollar. Fractions of a penny actually, compared to what vendor costs are.

We want our cake and we want to eat it too. Could Polaris build a motor that goes 10,000 miles without any rebuilding of anything? Probably. But it'd probably cost 3x as much or it'd put out 1/2 as much power.

We want supercar-esque performance in the mountains, and we want it for under $10K. All the manufacturers have to strike a balance between cost, reliability and performance.

This is also why competition is good. So far as I can tell, nobody has a clear edge when it comes to this. Every sled has its strength and weakness. If history is any guide, when performance begins to equalize (it already has) the next place the market goes is toward more reliability then lower costs.

Scoff as you might at snowmobile cost. Even on an inflation adjusted basis they are up about 50% from the early 80s. I'm fairly certain we don't want to incur even higher costs...right?

We get an incredible amount of technology at that price point. Be thankful. Marvel at modern capitalism and free markets. I do.

 

[JJ_0909]

BTW, as far as the honing being bad bla bla bal. Dan's sample size is ONE. ONE! And we are trusting one guy to chime in on this.

My instinct says "right or wrong, basing an opinion on a sample size of one is a surefire way to look like a fool..."

 

[shattuck]

BTW, as far as the honing being bad bla bla bal. Dan's sample size is ONE. ONE! And we are trusting one guy to chime in on this.

My instinct says "right or wrong, basing an opinion on a sample size of one is a surefire way to look like a fool..."

This is coupled with the reports of a few seized motors and very low snow conditions for most places so not much riding. I got my money on problems with the motor but you could possibly be right everything might be fine.

 

[mattymac]

Dan, you make it seem that the big block and the small block only differ in rod length. We,both, know this is not true. there are many differences that are in play with this topic.

1) Very important. The small block engine does not have 360 degree crank rotation piston skirt support. There are many degrees of rotation where the piston is not fully supported by the cylinder. This causes added side loads, especially, when the piston changes direction at bottom dead center. This is one of the major reasons why the pistons wear.

2) HP differences. You did mention this. The big block engine was capable of very high power output, when modified. You know as well as anybody, once you got the power up on the big block to where it is with the small block, this engine was spitting pistons and bearings and even stretching the cylinder bolts. It was anything but reliable once its power was matched to the current small block. Power is a key player with engine durability. Increase power, you decrease engine life and all internal components will be under more stress.

More stress equals less life.

Stating that the hone finish is a major reason why the big block lasted longer is a stretch and you know it.

Lesser power and more piston support is why it would last in stock form. Again, when this engine was pumped up, it was far from reliable.

You can not compare until the power outputs are equal.

There are many more differences and you know this.

In regards to HP differences, your statement claims that more HP means more wear? Of course I agree with that if all things are equal (same motors) when comparing two different motors then thats a whole different variable!

Funny I have cat 800/900/1000 twins that make more HP per cc than the polaris motors do yet theres no argument that cat/suzuki builds a more reliable engine.

I have built numerous 1200 watercraft polaris based sled engines over the years, my first (and still owned to this day) has 5000+ miles on it and that engine has never been apart! turns 85-8600 RPM has the small PTO end, makes 230 HP (75+hp per hole if you want to get technical or around 15% more per cyl than a stock 800 VES carbed twin but similar to a cfi 800 and you claim they dont last in your post?) yet Ive never seen a polaris BB VES twin in stock form go more than 2000 mountain miles without having crank issues. I personally attribute much of that to premixing my triple... if its getting fuel to run, its getting oil to lube! Theres also no direct oil being pumped onto the outboard bearings like the twins, yet just like the energizer bunny my triples keep going and going.

wasnt trying to get off topic from the original post but nickel silicone carbide is extremely hard! Pistons and rings are not as hard. Also nicasil is very porous or rough. These are facts!

I could imagine taking a piece of medium/coarse sandpaper laying it on a workbench flat pouring oil on the rough surface then running your hand up and down against the sandpaper. Sandpaper is porous yet oil will hold on the rough surface better although your skin isnt as hard as the silica on the paper thus you will eventually wear down your skin.

 

[ADDIE]

When you have more surface contact area with a smoother finish, you have more friction. This is true with anything not just engines. More surface contact = more friction.
One could make the case that the finer the honing finish, the more surface contact with the piston ring. Which brings up another point, the ring is really the main and only component that is doing any work. When an engine fails, it is due to the oil barrier failing and the ring having metal to metal contact (no oil) , friction sky rockets and galling occurs in very short order.

Just another view

 

[JJ_0909]

This is coupled with the reports of a few seized motors and very low snow conditions for most places so not much riding. I got my money on problems with the motor but you could possibly be right everything might be fine.

Those reports seem very shaky. I know zero first hand. And despite all these threads, there is very little concrete evidence of people jumping in with real world "my sled blew up, here ya go".

We know one blew up because an oil line came off. That's not a motor design issue. That's just a simple "whoops".

We know of another that had some form of a top end failure? Right? But then again, didn't that poster take everything down and post pictures of a double ring piston?

There is a lot of chatter on a lot of unicorn farts so far as I can tell. Polaris sold 850s in the thousands. Not hundreds. Doing some rough estimations, Polaris sells about 30K units a year. Lets just say 1/4 were 850s? Or lets say 1/5th or 1/6th?? Either way, we're in the thousands....

So 1-3 failures out of thousands of sales...not sure we should be panicking.

 

[JJ_0909]

When you have more surface contact area with a smoother finish, you have more friction. This is true with anything not just engines. More surface contact = more friction.
One could make the case that the finer the honing finish, the more surface contact with the piston ring. Which brings up another point, the ring is really the main and only component that is doing any work. When an engine fails, it is due to the oil barrier failing and the ring having metal to metal contact (no oil) , friction sky rockets and galling occurs in very short order.

Just another view

Not an engine builder. Am a suspension nerd. It is well established overly smooth stanctions (friction) create more stiction than something with a rougher anodization. In fact, you can send your moto stuff to a number of tuners, such as Kreft, to have them put a microscopic crosshatch into the material for smoother performance. It 100% works. Longer seal life. Better performance. More lubrication of important parts (bushings/seals).

We are all under this assumption that somehow Dan's honing is the best. Based on what? Proven by who? Not saying he's wrong, I'm just saying its silly for everyone to jump on board without some bit of skepticism around this idea.

 

[Spaarky]

Number I heard was 10,000 850’s. Just rough math that seems a little high, but I do not know what some of the bigger dealerships were allowed. Plus the demos.

 

[JJ_0909]

Number I heard was 10,000 850’s. Just rough math that seems a little high, but I do not know what some of the bigger dealerships were allowed. Plus the demos.

Seems reasonable. I was really ballparking it. I have to dig through a lot of channel checks to get even a half way reliable number. Either way, I think we can all agree its probably between 5-12K.

 

[Spaarky]

Jj... I am sure you won’t believe me. We(our riding crew) have seen the good bad and ugly of the honing. Dans hg7 has shown spectacular results for us.

We haven’t been best buds in the past, so if you want more info, pm me and we can discuss it. I can give you our experiences. We were on the front end of the ugly.