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2021 pistons


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#1 Z-809

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Posted 22 July 2020 - 10:13 PM

 The 850 Piston number for the 2021  is different then previous. Did BRP make a change to the piston??



#2 krm

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Posted 23 July 2020 - 03:11 AM

Could just be a new vendor



#3 Meat Head

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Posted 23 July 2020 - 02:53 PM

Fastest 850 ever due to new secret pistons.. its a fact.

#4 Gin la pine

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Posted 24 July 2020 - 07:19 AM

3d printed piston  :D



#5 vinci_78

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Posted 24 July 2020 - 03:58 PM

Yes. The pistons changed from the 420893791, used in 2020 to the 420893796 for the 2021 850s (including the turbo 850) This was the reason for the change/upgrade imo. Strangely the new piston assy 420893796 is $50 cheaper. 

 

Any other questions?



#6 Meat Head

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Posted 24 July 2020 - 04:11 PM

Yes. The pistons changed from the 420893791, used in 2020 to the 420893796 for the 2021 850s (including the turbo 850) This was the reason for the change/upgrade imo. Strangely the new piston assy 420893796 is $50 cheaper.

Any other questions?

Lighter weight means less cost on material=faster..

#7 vinci_78

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Posted 24 July 2020 - 04:14 PM

Who said it was lighter? 



#8 krm

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Posted 25 July 2020 - 06:31 AM

Yes. The pistons changed from the 420893791, used in 2020 to the 420893796 for the 2021 850s (including the turbo 850) This was the reason for the change/upgrade imo. Strangely the new piston assy 420893796 is $50 cheaper. 

 

Any other questions?

Smarter $$ wise.One piston for two applications ..I;d say more like yamaha pistons that are able to control heat .



#9 syracusestars37

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Posted 27 July 2020 - 01:55 PM

The turbo piston need be no different than the N/A 850 - Its not building boost at sea level and therefor shouldnt need a static compression adjustment.



#10 Mach21

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Posted 02 August 2020 - 01:06 AM

So is it(the new piston) an upgrade? Or not?

#11 syracusestars37

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Posted 04 August 2020 - 08:57 AM

So is it(the new piston) an upgrade? Or not?

Sure?

 

Ha, nobody can really say that without having one of each in front of them to compare. Material properties, ring location pins, wrist pin area, ect.

 

Honest opinion from somebody in a similar field? It is likely a cost reduction. Be it a new supplier, material changes, ect. Tooling isnt cheap so there must be a darn good reason for a change, and thats usually cost driven or some design flaw they're correcting for.



#12 Daag44

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Posted 04 August 2020 - 09:22 AM

Maybe a forged piston? Just kidding, that was a goof-up in an early pamphlet lol



#13 Mach21

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Posted 04 August 2020 - 09:59 PM

Sure?
 
Ha, nobody can really say that without having one of each in front of them to compare. Material properties, ring location pins, wrist pin area, ect.
 
Honest opinion from somebody in a similar field? It is likely a cost reduction. Be it a new supplier, material changes, ect. Tooling isnt cheap so there must be a darn good reason for a change, and thats usually cost driven or some design flaw they're correcting for.


Well, if it’s a design flaw they’re correcting for, then it’s definitely an upgrade compared to the previous piston, cuz they’re correcting the flaw. But you’re probably right with the cost reduction idea instead.

Hmm I’m curious especially since I have one(an 850 2021) ordered.

#14 djm

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Posted 04 August 2020 - 10:32 PM

Well, if it’s a design flaw they’re correcting for, then it’s definitely an upgrade compared to the previous piston, cuz they’re correcting the flaw. But you’re probably right with the cost reduction idea instead.

Hmm I’m curious especially since I have one(an 850 2021) ordered.

 

My guess is you are really concerned you could call Trystad or Big John and ask. if not big John, I am sure Dave has been using the new one.   I suspect they may have had one or two in hand already.

 

Don't think there has been any issue with 2017-2020 850 pistons that we have heard about.  So unless they did something to accomodate the turbo 850 that impacted the regular 850; It is a probably a cost reduction or a print change to make the drawing like the part that was being manufactured.  We do that often in the auto business.. Parts aren't quite to print.. if the part not to print is functioning well, they will often update a drawing to be the same as the part they are using and roll the part number.   



#15 Daag44

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Posted 05 August 2020 - 01:02 AM

Is design change and design flaw the same thing?

 

BRP are hard up on quality, so I can't see them changing suppliers unless there is a major problem that directly affects warranty claims. I have yet to see any signs of problems with the pistons, so I don't see any hint of this happening. So with the same supplier, how would any lower cost translate to a different part number?

 

I'm with Ken that a part number change was more likely an update. Was it an update to fit both NA and turbo? If the part number is the same for both, then I would guess it was an update. Like DJM said, I haven't heard of a problem with the pistons on the NA engine. Have any of you?






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