I haven't the faintest idea what the handling of a Harley have to do in a Polaris sled thread, but anyhow, good that you are aware of this potential issue.
850 gone down already??
- Thread starter ANTHONY11
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Some cranks were notoriously out of phase on the 800ho and R, new or rebuilt. Just a really sensitive motor to crank phasing with the factory porting. Phase, polish and raise ports a tad, cut the head 0.010, and every single one would rip.
12% year 1 failure rate would be seen as catastrophic inside poo. To the point they would be booking significant reserves for years 2-4. We're talking screaming and long knives in the management review meetings.
The rod looks good. Is there an oil slot on both the exhaust and intake side on the big end? I can imagine a fixture with 4 guide posts to press the crankpins straight. Can you get a crank of a twin assembled under 2 thou with fixtures?
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In the third and fourth year of the 800R the crank bearings on the 800R were given more internal clearance for the centers and pto end (outer one). By the time the 800RE (ETEC) came out in 2010.5 the issues with the crankshaft bearings had been worked-out, including stronger connecting rods.
Note: 800R is a Type 797. So it if says 800R or 797 it is the same engine, just the way they wrote it for each section. And the 800R ETEC is an 800R/797.
Also note the wording "in certain conditions" and "in severe conditions". This is exactly what IndyDan has talked about some years back when the poo pto end bearings were seizing... in certain conditions. Dan is the only one I found who talks about internal/radial bearing clearance. The man is brilliant.
2008 Type 800R
What's New: 10 Microns lager bore diameter around center and mag side main bearing bores.
Why: This added clearance reduces the "squeeze" or "clamping pressure" on these bearings, which in turn reduces the bearing's internal friction an improves bearing life in certain conditions.
The letter "R" stamped near PTO injection nipple denotes larger bore.
2009 Type 797
What's New: Center main bearings are now with integrated seals and C5 bearing fit.
Why: C5 bearing versus C4 means more radial clearance and also center bearings are now grease filled with integrated seals. Similar to outside main bearings, no lubrication ever needed. Designed for improved durability.
2010 Type 797 and 800R
What's New: Ball bearing (PTO side)
Why:A C5 fit bearing, meaning "more radial clearance" and improved material to increase durability in severe conditions. Similar to center main bearings introduced in MY 2009.
It failed during break-in. Piston runs too hot, oil film breaks down and risk of coolant ingestion through the head o-rings. These engines get torn down without a proper engine leak test. We are in a rush to take them apart to see how they look, then most of the evidence is gone.
The real cool thing about the Patriot is the cylinder and head cooling, and the fuel pressure sensor. So it was likely not a fuel pump issue.
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what happened in pic #1?
S
snowmobiler
Well-known member
dryed piston goo
Thank you Daag44' yes I cut a oil slot on both sides.
Back in the 900 days they only had a slot on the exhaust side.... As did ski doo.
Pretty sure they were trying to hold oil inside the rod.
When I built The Ski doo 800 XM rods I made some with one slot and some with two slots..... Never had problem with either so I am pretty sure in the end 2 slots is a little safer.
As for the fixture for the 850..... I have not built it yet.
The 800 small block is the only crankshaft I built a speed assembly fixture for because we do so many of them.
I will be building a completely new design for the 850 crank.... I hope to see .0005 to .0015 straight out of the fixture.
Might be a stretch but I am hoping for the best..... Tough to over expect with C4 fit center bearing... Might be more like .002 to .004 out of the fixture then have to hand true them from there.
Hey ! Thanks for remembering the bearing interference fit and internal radial clearance threads
Internal bearing clearance is not common bearing knowledge ..... Most people check I.D. And O.D. And think a bearing is a bearing.
Not many people knew what I was talking about.
Dan
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Sorry I got off track.....I always wanted a Harley but every time I drive one for any distance I just can't make myself do it.....I feel completely unsafe on the newer Harley's in aggressive corners.
I have 900 plus Pound Pig Victory Vision and it's like a slot car in the corners comparatively speaking.
I am still mad at Polaris for killing the Victory ..... I was set to buy a new Vision in the 2019 ..... But we all know where that went.
Now I am lost...... Seriously thinking BMW
Just can't see myself trying to wish my way around a corner on a Harley.... To dangerous for a wreckless driver like me.
Dan
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Well Dan if your going to be investing in the 850 in a big way I think I’m going to wait awhile till the dust settles then pick up a clean 2nd hand one and take advantage of your aftermarket parts. In my humble opinion this 850 has the potential to be the benchmark Polaris sled for years to come. You mentioned possibly casting your own cylinders, if so could there be a displacement increase?
I have been a loyal Polaris customer since forever for me I have also been as loyal as possible to the closest dealer for me which was Vetters in Kasota Jerry and pretty much all the guys there know you by name and treat you like your there #1 customer, service to me is #1 as long as the price is reasonably close, unfortunately Jerry is no longer running the business but sounds like most his guys who are awesome will be working at another dealer close by anyways where I was going with this is I went to the sneak peak last year to check out the new 850 I was about to purchase and thought it was kind of a big f you to all the little dealers that Polaris let one big dealer be at the show and try to get sales and have there name plastered all over, nothing against that dealer they might be great guys to buy from just didn't seem right to me
Jay it's definitely going to be a great motor quickly.
As far as more displacement.... From my point of view no.
The crankshaft just isnt't long enough for more bore size..... However it could easily be stroked by building a new crankshaft.
I personally wouldn't do that either..... I really like the combo 74x85
If a guy did stroke it, It would be really dangerous IMO to go past 76mm....... And that would be a very expensive 2mm.
80mm would turn it into a vibrating pile of junk...... ( yes I know the 850 Ski Doo is a 80mm stroke motor ) I am not a fan of that much stroke..... Don't get me wrong..... It can be done effectively but doing it in a light-weight configuration is just about impossible.
The 850 crankshaft is almost exactly the same length as the 800 Small Block crank..... They just robbed length from the MAG end and narrowed up the MAG bearing and put that extra width in the middle to give alittle more separation between centers.
Then Polaris copied the ski doo mono cylinder and went from 8 cylinder bolts down to 6 to give the cylinder more water flow around the exhaust port.
IMO any move to big bore or stroke this motor will lead to a sad customer in the end..... I will never go there with this motor.
I am to old to deal with the wrath of problems that come with stretching a motor that's physically to short to go bigger.
Dan
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Great post Butcher !!
Hey Bud......You just said a BIG mouthful here !
How did the Arctic Cat Gander Mountain gig turn out ??
Bean counters sitting around a circle jerk ( looking for a pivot man ) trying to figure out the next great way to screw the masses..... And act like they are doing us all a favor at the same time.
I got news for these types of corporate morons..... There is a under ground revolution coming that is going to teach these big corporations that we the people can't be pushed around as easy as before.... ( the power of the Internet ) is two fold.
They think they can control us with limited parts availability and massive retail prices on the few parts they do offer.....and force us into buying the next great model......because stopped building parts 7 years ago... - ( The 2019 Polaris 850 crankshaft parts break down offers basically ZERO replacement parts availability ) ......its a sign of the screwing they are about to give us all in their own corporate way.
We can't let it happen.
The private Polaris owns group is coming...... I am going to expand our machine shop to a level Polaris might not think possible.
Within the next 5 years Indy Specialty LLC will be the largest private Polaris OEM piston supplier in the United Sates and prices will Most likely be less then Polaris and quality better..... And instead of ripping people off with over priced OE parts people can buy fun stuff like Turbos and clutch kits and so on.
What people fail to see in this business from first glance...... Imagine the forward thinking and energy bottled up that people have been putting into new 850 Polaris parts 6 months ago....
Now thanks to Polaris and their careless ways....... All aftermarket parts growth has been given a death blow because people are spooked..... And many will now hold back on trying new stuff.
Polaris has interrupted the entire Ebb & Flow of a new model release.
But..... I am going to do my best this summer to gear up for the best second season a new model can have.
There is one really really great thing about the few 850 mishaps...... This should allow the 800 Small Block to live a few more years.
It would be ashame for that motor to go away when it's just finally finding its sweet spot in the market..... ( Plus I have a pile of parts for those motors )
Plus it will give everyone time to get up to speed on the 850 without help from Polaris.
It's time we all go full " John Wick " on Polaris and their secret scam to not sell OEM crankshaft parts separately.
It will be incredibly complex to produce crankshaft parts competitively in the United States in a Small private machine shop because of the cost of material resources, lack of huge capital money and wages compared to LUNG KU in Taiwan.
But we are sure going to make a go at it.
Maybe We crash and burn.....You Never know, I am sure Polaris will do everything they can to make sure we fail.
Dan
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I never realized the oil slot on the 900 was on the exhaust side. It's on the intake side for the Ski-Doo on at least the Series III and later.
Ski-Doo explained they used two slots for the 800R for better oiling. It was a tricky explanation when considering they kept only one on the intake side for their 600s. Most aftermarket rebuilt Ski-Doo cranks for the 800R use Wossner rods, and for some strange reason they give only one slot on the intake side.
A new crank design for the 850 should be sweet. There always seems to be room for improvement with rod ratios and placement of the crank bearings. Looking at the 900 crank there is quite a distance between the two pto bearings. At first glance it appears to provide added support, but I believe this causes a pivot point at the inner bearings. This is about the mid point between the center pto and the clutch. Could this be adding stress to the outer pto bearing? Maybe it is one the reasons for the success of the double row cylindrical bearings.
The change from direct oiling of the center bearings raises a question mark. Consider Ski-Doo changed from a mist to grease on the 800R, and then to a direct oil feed on the 850. Why would Polaris be doing the opposite?
Benchmark? Like the 900 and 800 dragon? The Axys chassis is definately a benchmark, the engines powering them are much less than "benchmark" status.
Should be an interesting time. I will be watching to see if Dan can attract enough consumers to float the whole shebang. If the 850 motors continue to fail at a high rate, resale on the benchmark 850 Poo sleds is going to tank HARD. Now you will be asking consumers to pony up another $3500 for an Indy Spec motor. I am not sure the market is that large for a $3500 upgrade. At some point the excellent chassis just isn't enough to support the costs required to keep it on the snow and reliable.
The guys willing to drop big coin for a good motor seems like a long shot bet to me. These are the guys who can and will just replace the sled with new, and often with another brand before they drop almost 4 grand into updating a non-current model.
Personally I don't find the chassis so much better than the rest that I would be a candidate for this program. For that kind of money you can easily improve the other brands to be just as good if not better. Then there are those of us who just prefer stock, and that is probably the majority of sled buyers. If the 850 leaves them high and dry, many will just bail out. I do not have any desire to "ride this out", wait for Poo to build a decent motor or drop the cash for Dan to fix it. All of that is just way more hassle than I want from my sledding experience especially when the competition is so close.
I wish Dan the best and consider it a noble endeavor to stick it to Polaris a little bit, they have it coming... Just not so sure about this becoming any kind of benchmark except maybe as the biggest Polaris fail yet.
I think we can thank Harley Davidson for this push on dealers. My Yamaha and Harley dealer were together. He would order more Harley's than anyone else in the nation put them in storage and he would be the only one with stock to sell. He charged more than retail and made it big. Harley came it told him Yamaha could not be on floor with Yamaha. Wall was put up to split showroom he was making huge money so why not. At this time still largest dealer for Harley sales. Next year Harley told him he needs to move to a better location with a 2 million dollar store and no Yamaha. His location had been same for 30 years his customers new where to find him even before internet. His parts inventory for both was off the charts compared to any dealer today. I bought several yamhas and Harley's. I bought 11 motorcycles and 14 sleds from this dealer. His service was great. He did not make the move and closed up and retired he was 70.
The chasis is a bench mark since 2011 NONE of the competition can come close to weight and handling in deep snow.
