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Redesigned 850 Crankshaft

You guys are starting to scare meo_O My sled turns 8700 with the BD high boost kit with 1600 miles on it.
 
I think the ECU doesn’t get a proper signal from the flywheel when rotation is interrupted for that micro second.
I expected a backfire in the the pipe that reversed the flow back into the motor.
 
You guys are starting to scare meo_O My sled turns 8700 with the BD high boost kit with 1600 miles on it.
I believe a turbo will let it live longer. Cooler intake temps, less consistent full throttle load, case pressure supports the piston, auxiliary injectors help cool the piston and allow a solvent to move lubricant.
My thoughts.
 
Yes. The locating pin migrates in, the ring spins on the piston and catches the exhaust port.
I have had this issue on 800’s and 850’s.
All from 300-800 miles per engine.
The last 850 engine made it just under 1100 miles, but failed a leak down test around 750 miles. We kept dropping fly weights until it went down. Polaris moved from a historic 5% leak rebuild to 10%. I think the bean counters made this decision to get past warranty claims before they pass it on to the insurance company.
You can tell when a ring starts it’s migration, you will get a audible pop and the engine shuts down. It will start up, but the inevitable has started.

I had the same piston failure, ring cought port, cost me 1200$ chopper bill. Warranty covered a new motor.
Tony, do u think they fixed this ring / pin issue?
 
I had the same piston failure, ring cought port, cost me 1200$ chopper bill. Warranty covered a new motor.
Tony, do u think they fixed this ring / pin issue?
I don’t. Sorry to say.
It started in my 800’s and the 850 has the same issue. Let’s see what the Boost piston has to offer.
Doo had the same issue when the etec came out. A Doo engineer was flown here to see where the piston failure occurred. Jim had the first one to go down. They had multiple design pistons in the first year of production. I believe they got that fixed.
 
I don’t. Sorry to say.
It started in my 800’s and the 850 has the same issue. Let’s see what the Boost piston has to offer.
Doo had the same issue when the etec came out. A Doo engineer was flown here to see where the piston failure occurred. Jim had the first one to go down. They had multiple design pistons in the first year of production. I believe they got that fixed.
Depends on the rider, Ive got one guy that will do it in under 1000 miles on every piston except a Suzuki.
Rev 800s were every 5-700.
The best fix so far is three sleds and keep them all under warranty.
His Doo turbo hasnt gone down yet so well see on that one.
 
One of my 19’ 850 made one day before the pto bearing welded itself to the crank, my other 19’ 850 has close to 1500 trouble free miles on it.
 
One of my 19’ 850 made one day before the pto bearing welded itself to the crank, my other 19’ 850 has close to 1500 trouble free miles on it.
That is about how long they will last without oil flow.
 
Depends on the rider, Ive got one guy that will do it in under 1000 miles on every piston except a Suzuki.
Rev 800s were every 5-700.
The best fix so far is three sleds and keep them all under warranty.
His Doo turbo hasnt gone down yet so well see on that one.
The piston locators coming out has a lot to do with the rider..... The cylinder finish on a Polaris is still a little to aggressive.

( Tony is bat-sh!t full throttle crazy ) Full throttle Down Hill ) ........ring locators will never stay in place with a OEM cylinder finish........ ???

if you hold the throttle wide open relentlessly for long periods of time the ring starts to glow and the ring anti rotation pin gets to hot and it moves.

Our latest HG7 cylinder finish eliminates this problem.

We do not have locator problems in our motors

Dan
 
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Sorry, I forgot to address the Polaris ( Stop Sale order )

It seems Polaris let this turn into a comedy of errors ( As far as letting the dealers and the consumer know the exact problem ) Maybe because they really do not know the exact problem..... ??‍♂️

Why not say the exact problem right away ?

In the beginning 2 - Rumors were started.....

1 - PTO bearing problem.

2- Center bearings Problem.

Later, ( 3 ) - We hear it’s a Lower connecting Rod bearing retainer production defect.......

The problem is so bad the failure is almost instant we have been told......

I want to make it clear about the reason Indy Specialty Built a Redesigned Crankshaft..... ( Nothing to do with the Stop order )

In 2018 when I tore down my new 2019 850 Indy XC...... and saw the PTO-end design with the use of the roller bearing ( ( This is when I decided it had to be changed. )

Making a completely Billet Crankshaft from scratch in a Privately owned relatively Small Machine Shop with Conventional CNC Milling Machines and Lathes ( Not that it could not be done with the equipment we had ..... ) Maybe not the best way.

We needed more advanced machine such as a Mill / Turn Machine.

So the search for a Big Rigid Machine began.

Fast forward to 2022 Snow season, We purchased a Machine in 2019 and we are now building all components for the Polaris 850 Crankshaft.

Back to the ( Polaris Stop Sale Order ) - At this point I do not believe Polaris knows what’s wrong ..... I know of 7 New 2022 Matrix 850‘s That went down in the past 2 weeks on the first ride in Canada.

This leads me to believe that whoever trouble-Shot the problem was not sure of the problem or the fix was not done correctly.

If we have a great winter with lots of Snow ( Polaris’s Quick fix is going to be tested to a degree they might not expect.)

In my opinion...... The only reason more crankshaft problems have not surfaced is because the last 3 years the snow has not been very good and the riding has been far less then normal.

I do believe the fix ( For the 850 that failed in a few seconds on the dyno ) has not been resolved......Or the point in production where they thought the problem was Started ...... was much wider number then they thought.

( Building a crankshaft from scratch is a slow process that has been going on for close to 3 years ) Which had nothing to do with a Stop Sale order.

If anything I said is confusing let me know...... Tech writing is not my specialty.

Dan
 
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6200 miles on my 850 and the crank bearing seized up still under warranty haven’t brought into dealer yet! First failure was a piston at 2300 miles whole new topend covered.
 
Only thing I have to add to this thread is that I'm jealous of you guys (Indy Dan and TRS) that get to ride enough to test and find out these long-term problems!
 
Ok, I need to clear up a few things in my last post.

I mentioned that I knew of 7 new 2022 850 Matrix’s that went down....

And I said I did not think Polaris knew what the real problem was...... I have since been informed that some sleds slipped out and never got updated with new motors......They were shipped before the problem was known.

And that Polaris has got the problems resolved , I was told that a major problem has been the ( FJB Let’s Go Brandon supply Chain. ) This is the reason all parts should be made in the U.S.A.

If you voted for Biden your voting privileges should revoked for 8 years.

Back on point

So I want to apologize to Polaris & everyone for causing any concerns and nervousness about the updates being preformed.

I have been informed that the problems found have been pin pointed and are being taken care of as fast as possible.

Dan
 
I think we were led to believe the Stop Sale was on 850 Axys sleds and not the Matryx. Then the conclusion of the Axys having the engine issue would be disrupted if the Matryx had faulty engines.

yes, Exactly correct and that’s why I posted what I posted.... 7 Matryx sleds going down on their first week end seemed to point out that there wasn’t a real good pin point on the effected sleds.....

Dan
 
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